diff --git a/packages/backend/src/core/activitypub/ApDeliverManagerService.ts b/packages/backend/src/core/activitypub/ApDeliverManagerService.ts
index 5d07cd8e8..f045333d2 100644
--- a/packages/backend/src/core/activitypub/ApDeliverManagerService.ts
+++ b/packages/backend/src/core/activitypub/ApDeliverManagerService.ts
@@ -5,6 +5,7 @@
 
 import { Inject, Injectable } from '@nestjs/common';
 import { IsNull, Not } from 'typeorm';
+import { UnrecoverableError } from 'bullmq';
 import { DI } from '@/di-symbols.js';
 import type { FollowingsRepository } from '@/models/_.js';
 import type { MiLocalUser, MiRemoteUser, MiUser } from '@/models/User.js';
@@ -128,7 +129,7 @@ class DeliverManager {
 
 			for (const following of followers) {
 				const inbox = following.followerSharedInbox ?? following.followerInbox;
-				if (inbox === null) throw new Error('inbox is null');
+				if (inbox === null) throw new UnrecoverableError(`inbox is null: following ${following.id}`);
 				inboxes.set(inbox, following.followerSharedInbox != null);
 			}
 		}
diff --git a/packages/backend/src/core/activitypub/ApRendererService.ts b/packages/backend/src/core/activitypub/ApRendererService.ts
index 516da8d91..f61e27877 100644
--- a/packages/backend/src/core/activitypub/ApRendererService.ts
+++ b/packages/backend/src/core/activitypub/ApRendererService.ts
@@ -7,6 +7,7 @@ import { createPublicKey, randomUUID } from 'node:crypto';
 import { Inject, Injectable } from '@nestjs/common';
 import { In } from 'typeorm';
 import * as mfm from 'mfm-js';
+import { UnrecoverableError } from 'bullmq';
 import { DI } from '@/di-symbols.js';
 import type { Config } from '@/config.js';
 import type { MiPartialLocalUser, MiLocalUser, MiPartialRemoteUser, MiRemoteUser, MiUser } from '@/models/User.js';
@@ -30,6 +31,7 @@ import { IdService } from '@/core/IdService.js';
 import { JsonLdService } from './JsonLdService.js';
 import { ApMfmService } from './ApMfmService.js';
 import { CONTEXT } from './misc/contexts.js';
+import { getApId } from './type.js';
 import type { IAccept, IActivity, IAdd, IAnnounce, IApDocument, IApEmoji, IApHashtag, IApImage, IApMention, IBlock, ICreate, IDelete, IFlag, IFollow, IKey, ILike, IMove, IObject, IPost, IQuestion, IReject, IRemove, ITombstone, IUndo, IUpdate } from './type.js';
 
 @Injectable()
@@ -100,7 +102,7 @@ export class ApRendererService {
 			to = [`${attributedTo}/followers`];
 			cc = [];
 		} else {
-			throw new Error('renderAnnounce: cannot render non-public note');
+			throw new UnrecoverableError(`renderAnnounce: cannot render non-public note: ${getApId(object)}`);
 		}
 
 		return {
diff --git a/packages/backend/src/core/activitypub/ApResolverService.ts b/packages/backend/src/core/activitypub/ApResolverService.ts
index 42391d726..d4964d544 100644
--- a/packages/backend/src/core/activitypub/ApResolverService.ts
+++ b/packages/backend/src/core/activitypub/ApResolverService.ts
@@ -5,7 +5,7 @@
 
 import { Inject, Injectable } from '@nestjs/common';
 import { IsNull, Not } from 'typeorm';
-import * as Bull from 'bullmq';
+import { UnrecoverableError } from 'bullmq';
 import type { MiLocalUser, MiRemoteUser } from '@/models/User.js';
 import { InstanceActorService } from '@/core/InstanceActorService.js';
 import type { NotesRepository, PollsRepository, NoteReactionsRepository, UsersRepository, FollowRequestsRepository, MiMeta } from '@/models/_.js';
@@ -16,12 +16,12 @@ import { UtilityService } from '@/core/UtilityService.js';
 import { bindThis } from '@/decorators.js';
 import { LoggerService } from '@/core/LoggerService.js';
 import type Logger from '@/logger.js';
+import { fromTuple } from '@/misc/from-tuple.js';
 import { isCollectionOrOrderedCollection } from './type.js';
 import { ApDbResolverService } from './ApDbResolverService.js';
 import { ApRendererService } from './ApRendererService.js';
 import { ApRequestService } from './ApRequestService.js';
 import type { IObject, ICollection, IOrderedCollection } from './type.js';
-import { fromTuple } from '@/misc/from-tuple.js';
 
 export class Resolver {
 	private history: Set<string>;
@@ -68,7 +68,7 @@ export class Resolver {
 		if (isCollectionOrOrderedCollection(collection)) {
 			return collection;
 		} else {
-			throw new Error(`unrecognized collection type: ${collection.type}`);
+			throw new UnrecoverableError(`unrecognized collection type: ${collection.type}`);
 		}
 	}
 
@@ -85,15 +85,15 @@ export class Resolver {
 			// URLs with fragment parts cannot be resolved correctly because
 			// the fragment part does not get transmitted over HTTP(S).
 			// Avoid strange behaviour by not trying to resolve these at all.
-			throw new Error(`cannot resolve URL with fragment: ${value}`);
+			throw new UnrecoverableError(`cannot resolve URL with fragment: ${value}`);
 		}
 
 		if (this.history.has(value)) {
-			throw new Error('cannot resolve already resolved one');
+			throw new Error(`cannot resolve already resolved URL: ${value}`);
 		}
 
 		if (this.history.size > this.recursionLimit) {
-			throw new Bull.UnrecoverableError(`hit recursion limit: ${this.utilityService.extractDbHost(value)}`);
+			throw new Error(`hit recursion limit: ${value}`);
 		}
 
 		this.history.add(value);
@@ -104,7 +104,7 @@ export class Resolver {
 		}
 
 		if (!this.utilityService.isFederationAllowedHost(host)) {
-			throw new Bull.UnrecoverableError('Instance is blocked');
+			throw new UnrecoverableError(`instance is blocked: ${value}`);
 		}
 
 		if (this.config.signToActivityPubGet && !this.user) {
@@ -120,7 +120,7 @@ export class Resolver {
 				!(object['@context'] as unknown[]).includes('https://www.w3.org/ns/activitystreams') :
 				object['@context'] !== 'https://www.w3.org/ns/activitystreams'
 		) {
-			throw new Error('invalid response');
+			throw new UnrecoverableError(`invalid AP object ${value}: does not have ActivityStreams context`);
 		}
 
 		// HttpRequestService / ApRequestService have already checked that
@@ -128,12 +128,12 @@ export class Resolver {
 		// object after redirects; here we double-check that no redirects
 		// bounced between hosts
 		if (object.id == null) {
-			throw new Error('invalid AP object: missing id');
+			throw new UnrecoverableError(`invalid AP object ${value}: missing id`);
 		}
 
-		// if (this.utilityService.punyHost(object.id) !== this.utilityService.punyHost(value)) {
-		// 	throw new Error(`invalid AP object ${value}: id ${object.id} has different host`);
-		// }
+		if (this.utilityService.punyHost(object.id) !== this.utilityService.punyHost(value)) {
+			throw new UnrecoverableError(`invalid AP object ${value}: id ${object.id} has different host`);
+		}
 
 		return object;
 	}
@@ -141,7 +141,7 @@ export class Resolver {
 	@bindThis
 	private resolveLocal(url: string): Promise<IObject> {
 		const parsed = this.apDbResolverService.parseUri(url);
-		if (!parsed.local) throw new Error('resolveLocal: not local');
+		if (!parsed.local) throw new UnrecoverableError(`resolveLocal - not a local URL: ${url}`);
 
 		switch (parsed.type) {
 			case 'notes':
@@ -170,7 +170,7 @@ export class Resolver {
 			case 'follows':
 				return this.followRequestsRepository.findOneBy({ id: parsed.id })
 					.then(async followRequest => {
-						if (followRequest == null) throw new Error('resolveLocal: invalid follow request ID');
+						if (followRequest == null) throw new UnrecoverableError(`resolveLocal - invalid follow request ID ${parsed.id}: ${url}`);
 						const [follower, followee] = await Promise.all([
 							this.usersRepository.findOneBy({
 								id: followRequest.followerId,
@@ -182,12 +182,12 @@ export class Resolver {
 							}),
 						]);
 						if (follower == null || followee == null) {
-							throw new Error('resolveLocal: follower or followee does not exist');
+							throw new Error(`resolveLocal - follower or followee does not exist: ${url}`);
 						}
 						return this.apRendererService.addContext(this.apRendererService.renderFollow(follower as MiLocalUser | MiRemoteUser, followee as MiLocalUser | MiRemoteUser, url));
 					});
 			default:
-				throw new Error(`resolveLocal: type ${parsed.type} unhandled`);
+				throw new UnrecoverableError(`resolveLocal: type ${parsed.type} unhandled: ${url}`);
 		}
 	}
 }
diff --git a/packages/backend/src/core/activitypub/JsonLdService.ts b/packages/backend/src/core/activitypub/JsonLdService.ts
index 100d4fa19..9d1e2e06c 100644
--- a/packages/backend/src/core/activitypub/JsonLdService.ts
+++ b/packages/backend/src/core/activitypub/JsonLdService.ts
@@ -5,6 +5,7 @@
 
 import * as crypto from 'node:crypto';
 import { Injectable } from '@nestjs/common';
+import { UnrecoverableError } from 'bullmq';
 import { HttpRequestService } from '@/core/HttpRequestService.js';
 import { bindThis } from '@/decorators.js';
 import { CONTEXT, PRELOADED_CONTEXTS } from './misc/contexts.js';
@@ -109,7 +110,7 @@ class JsonLd {
 	@bindThis
 	private getLoader() {
 		return async (url: string): Promise<RemoteDocument> => {
-			if (!/^https?:\/\//.test(url)) throw new Error(`Invalid URL ${url}`);
+			if (!/^https?:\/\//.test(url)) throw new UnrecoverableError(`Invalid URL: ${url}`);
 
 			if (this.preLoad) {
 				if (url in PRELOADED_CONTEXTS) {
@@ -148,7 +149,7 @@ class JsonLd {
 			},
 		).then(res => {
 			if (!res.ok) {
-				throw new Error(`${res.status} ${res.statusText}`);
+				throw new Error(`JSON-LD fetch failed with ${res.status} ${res.statusText}: ${url}`);
 			} else {
 				return res.json();
 			}
diff --git a/packages/backend/src/core/activitypub/misc/check-against-url.ts b/packages/backend/src/core/activitypub/misc/check-against-url.ts
index c8ad2ce58..edfab5a21 100644
--- a/packages/backend/src/core/activitypub/misc/check-against-url.ts
+++ b/packages/backend/src/core/activitypub/misc/check-against-url.ts
@@ -3,6 +3,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
+import { UnrecoverableError } from 'bullmq';
 import type { IObject } from '../type.js';
 
 function getHrefsFrom(one: IObject | string | undefined | (IObject | string | undefined)[]): (string | undefined)[] {
@@ -25,6 +26,6 @@ export function assertActivityMatchesUrls(activity: IObject, urls: string[]) {
 		.map(u => new URL(u as string).href);
 
 	if (!actualUrls.some(u => expectedUrls.has(u))) {
-		throw new Error(`bad Activity: neither id(${activity.id}) nor url(${JSON.stringify(activity.url)}) match location(${urls})`);
+		throw new UnrecoverableError(`bad Activity: neither id(${activity.id}) nor url(${JSON.stringify(activity.url)}) match location(${urls})`);
 	}
 }
diff --git a/packages/backend/src/core/activitypub/misc/validator.ts b/packages/backend/src/core/activitypub/misc/validator.ts
index 690beeffe..4292b7e0f 100644
--- a/packages/backend/src/core/activitypub/misc/validator.ts
+++ b/packages/backend/src/core/activitypub/misc/validator.ts
@@ -9,7 +9,7 @@ export function validateContentTypeSetAsActivityPub(response: Response): void {
 	const contentType = (response.headers.get('content-type') ?? '').toLowerCase();
 
 	if (contentType === '') {
-		throw new Error('Validate content type of AP response: No content-type header');
+		throw new Error(`invalid content type of AP response - no content-type header: ${response.url}`);
 	}
 	if (
 		contentType.startsWith('application/activity+json') ||
@@ -17,7 +17,7 @@ export function validateContentTypeSetAsActivityPub(response: Response): void {
 	) {
 		return;
 	}
-	throw new Error('Validate content type of AP response: Content type is not application/activity+json or application/ld+json');
+	throw new Error(`invalid content type of AP response - content type is not application/activity+json or application/ld+json: ${response.url}`);
 }
 
 const plusJsonSuffixRegex = /^\s*(application|text)\/[a-zA-Z0-9\.\-\+]+\+json\s*(;|$)/;
@@ -26,7 +26,7 @@ export function validateContentTypeSetAsJsonLD(response: Response): void {
 	const contentType = (response.headers.get('content-type') ?? '').toLowerCase();
 
 	if (contentType === '') {
-		throw new Error('Validate content type of JSON LD: No content-type header');
+		throw new Error(`invalid content type of JSON LD - no content-type header: ${response.url}`);
 	}
 	if (
 		contentType.startsWith('application/ld+json') ||
@@ -35,5 +35,5 @@ export function validateContentTypeSetAsJsonLD(response: Response): void {
 	) {
 		return;
 	}
-	throw new Error('Validate content type of JSON LD: Content type is not application/ld+json or application/json');
+	throw new Error(`invalid content type of JSON LD - content type is not application/ld+json or application/json: ${response.url}`);
 }
diff --git a/packages/backend/src/core/activitypub/models/ApImageService.ts b/packages/backend/src/core/activitypub/models/ApImageService.ts
index e7ece87b0..c80f98914 100644
--- a/packages/backend/src/core/activitypub/models/ApImageService.ts
+++ b/packages/backend/src/core/activitypub/models/ApImageService.ts
@@ -4,6 +4,7 @@
  */
 
 import { Inject, Injectable } from '@nestjs/common';
+import { UnrecoverableError } from 'bullmq';
 import { DI } from '@/di-symbols.js';
 import type { DriveFilesRepository, MiMeta } from '@/models/_.js';
 import type { MiRemoteUser } from '@/models/User.js';
@@ -43,7 +44,7 @@ export class ApImageService {
 	public async createImage(actor: MiRemoteUser, value: string | IObject): Promise<MiDriveFile | null> {
 		// 投稿者が凍結されていたらスキップ
 		if (actor.isSuspended) {
-			throw new Error('actor has been suspended');
+			throw new UnrecoverableError(`actor has been suspended: ${actor.uri}`);
 		}
 
 		const image = await this.apResolverService.createResolver().resolve(value);
diff --git a/packages/backend/src/core/activitypub/models/ApNoteService.ts b/packages/backend/src/core/activitypub/models/ApNoteService.ts
index 5f77e7d0b..523376c74 100644
--- a/packages/backend/src/core/activitypub/models/ApNoteService.ts
+++ b/packages/backend/src/core/activitypub/models/ApNoteService.ts
@@ -5,7 +5,7 @@
 
 import { forwardRef, Inject, Injectable } from '@nestjs/common';
 import { In } from 'typeorm';
-import * as Bull from 'bullmq';
+import { UnrecoverableError } from 'bullmq';
 import { DI } from '@/di-symbols.js';
 import type { PollsRepository, EmojisRepository, NotesRepository, MiMeta } from '@/models/_.js';
 import type { Config } from '@/config.js';
@@ -147,22 +147,21 @@ export class ApNoteService {
 		}
 
 		const note = object as IPost;
+		const url = getOneApHrefNullable(note.url);
 
 		this.logger.debug(`Note fetched: ${JSON.stringify(note, null, 2)}`);
 
 		if (note.id == null) {
-			throw new Error('Refusing to create note without id');
+			throw new UnrecoverableError(`Refusing to create note without id: ${entryUri}`);
 		}
 
 		if (!checkHttps(note.id)) {
-			throw new Error('unexpected schema of note.id: ' + note.id);
+			throw new UnrecoverableError(`unexpected schema of note url ${url}: ${entryUri}`);
 		}
 
-		const url = getOneApHrefNullable(note.url);
-
 		if (url != null) {
 			if (!checkHttps(url)) {
-				throw new Error('unexpected schema of note url: ' + url);
+				throw new UnrecoverableError('unexpected schema of note url: ' + url);
 			}
 
 			// if (this.utilityService.punyHost(url) !== this.utilityService.punyHost(note.id)) {
@@ -174,7 +173,7 @@ export class ApNoteService {
 
 		// 投稿者をフェッチ
 		if (note.attributedTo == null) {
-			throw new Error('invalid note.attributedTo: ' + note.attributedTo);
+			throw new UnrecoverableError(`invalid note.attributedTo ${note.attributedTo}: ${entryUri}`);
 		}
 
 		const uri = getOneApId(note.attributedTo);
@@ -183,7 +182,7 @@ export class ApNoteService {
 		// eslint-disable-next-line no-param-reassign
 		actor ??= await this.apPersonService.fetchPerson(uri) as MiRemoteUser | undefined;
 		if (actor && actor.isSuspended) {
-			throw new IdentifiableError('85ab9bd7-3a41-4530-959d-f07073900109', 'actor has been suspended');
+			throw new IdentifiableError('85ab9bd7-3a41-4530-959d-f07073900109', `actor ${uri} has been suspended: ${entryUri}`);
 		}
 
 		const apMentions = await this.apMentionService.extractApMentions(note.tag, resolver);
@@ -210,7 +209,7 @@ export class ApNoteService {
 		 */
 		const hasProhibitedWords = this.noteCreateService.checkProhibitedWordsContain({ cw, text, pollChoices: poll?.choices });
 		if (hasProhibitedWords) {
-			throw new IdentifiableError('689ee33f-f97c-479a-ac49-1b9f8140af99', 'Note contains prohibited words');
+			throw new IdentifiableError('689ee33f-f97c-479a-ac49-1b9f8140af99', `Note contains prohibited words: ${entryUri}`);
 		}
 		//#endregion
 
@@ -219,7 +218,7 @@ export class ApNoteService {
 
 		// 解決した投稿者が凍結されていたらスキップ
 		if (actor.isSuspended) {
-			throw new IdentifiableError('85ab9bd7-3a41-4530-959d-f07073900109', 'actor has been suspended');
+			throw new IdentifiableError('85ab9bd7-3a41-4530-959d-f07073900109', `actor has been suspended: ${entryUri}`);
 		}
 
 		const noteAudience = await this.apAudienceService.parseAudience(actor, note.to, note.cc, resolver);
@@ -249,25 +248,13 @@ export class ApNoteService {
 				.then(x => {
 					if (x == null) {
 						this.logger.warn('Specified inReplyTo, but not found');
-						throw new Error('inReplyTo not found');
+						throw new Error(`could not fetch inReplyTo ${note.inReplyTo}: ${entryUri}`);
 					}
 
 					return x;
 				})
 				.catch(async err => {
-					this.logger.warn(`Error in inReplyTo ${note.inReplyTo} - ${err.statusCode ?? err}`);
-					if (visibility === 'followers') { throw err; } // private reply
-					if (err.message === 'Instance is blocked') { throw err; }
-					if (err.message === 'blocked host') { throw err; }
-					if (err instanceof IdentifiableError) {
-						if (err.id === '85ab9bd7-3a41-4530-959d-f07073900109') { throw err; } // actor has been suspended
-					}
-					if (err instanceof StatusError) {
-						if (err.statusCode === 404) { return null; } // eat 404 error
-					}
-					if (err instanceof Bull.UnrecoverableError) {
-						return null; // eat unrecoverableerror
-					}
+					this.logger.warn(`error ${err.statusCode ?? err} fetching inReplyTo ${note.inReplyTo}: ${entryUri}`);
 					throw err;
 				})
 			: null;
@@ -298,7 +285,7 @@ export class ApNoteService {
 			quote = results.filter((x): x is { status: 'ok', res: MiNote } => x.status === 'ok').map(x => x.res).at(0);
 			if (!quote) {
 				if (results.some(x => x.status === 'temperror')) {
-					throw new Error('quote resolve failed');
+					throw new Error(`quote resolve failed: ${entryUri}`);
 				}
 			}
 		}
@@ -358,7 +345,7 @@ export class ApNoteService {
 			this.logger.info('The note is already inserted while creating itself, reading again');
 			const duplicate = await this.fetchNote(value);
 			if (!duplicate) {
-				throw new Error('The note creation failed with duplication error even when there is no duplication');
+				throw new Error(`The note creation failed with duplication error even when there is no duplication, ${entryUri}`);
 			}
 			return duplicate;
 		}
@@ -441,7 +428,7 @@ export class ApNoteService {
 		const uri = getApId(value);
 
 		if (!this.utilityService.isFederationAllowedUri(uri)) {
-			throw new StatusError('blocked host', 451);
+			throw new StatusError(`blocked host: ${uri}`, 451, 'blocked host');
 		}
 
 		const unlock = await this.appLockService.getApLock(uri);
@@ -453,7 +440,7 @@ export class ApNoteService {
 			//#endregion
 
 			if (this.utilityService.isUriLocal(uri)) {
-				throw new StatusError('cannot resolve local note', 400, 'cannot resolve local note');
+				throw new StatusError(`cannot resolve local note: ${uri}`, 400, 'cannot resolve local note');
 			}
 
 			// リモートサーバーからフェッチしてきて登録
@@ -501,7 +488,7 @@ export class ApNoteService {
 					});
 
 					const emoji = await this.emojisRepository.findOneBy({ host, name });
-					if (emoji == null) throw new Error('emoji update failed');
+					if (emoji == null) throw new Error(`emoji update failed: ${name}:${host}`);
 					return emoji;
 				}
 
diff --git a/packages/backend/src/core/activitypub/models/ApPersonService.ts b/packages/backend/src/core/activitypub/models/ApPersonService.ts
index abb68734d..bb56b1e90 100644
--- a/packages/backend/src/core/activitypub/models/ApPersonService.ts
+++ b/packages/backend/src/core/activitypub/models/ApPersonService.ts
@@ -7,6 +7,8 @@ import { Inject, Injectable } from '@nestjs/common';
 import promiseLimit from 'promise-limit';
 import { DataSource } from 'typeorm';
 import { ModuleRef } from '@nestjs/core';
+import { AbortError } from 'node-fetch';
+import { UnrecoverableError } from 'bullmq';
 import { DI } from '@/di-symbols.js';
 import type { FollowingsRepository, InstancesRepository, MiMeta, UserProfilesRepository, UserPublickeysRepository, UsersRepository } from '@/models/_.js';
 import type { Config } from '@/config.js';
@@ -139,19 +141,19 @@ export class ApPersonService implements OnModuleInit {
 		const expectHost = this.utilityService.punyHost(uri);
 
 		if (!isActor(x)) {
-			throw new Error(`invalid Actor type '${x.type}'`);
+			throw new UnrecoverableError(`invalid Actor type '${x.type}': ${uri}`);
 		}
 
 		if (!(typeof x.id === 'string' && x.id.length > 0)) {
-			throw new Error('invalid Actor: wrong id');
+			throw new UnrecoverableError(`invalid Actor - wrong id: ${uri}`);
 		}
 
 		if (!(typeof x.inbox === 'string' && x.inbox.length > 0)) {
-			throw new Error('invalid Actor: wrong inbox');
+			throw new UnrecoverableError(`invalid Actor - wrong inbox: ${uri}`);
 		}
 
 		if (this.utilityService.punyHost(x.inbox) !== expectHost) {
-			throw new Error('invalid Actor: inbox has different host');
+			throw new UnrecoverableError(`invalid Actor - inbox has different host: ${uri}`);
 		}
 
 		const sharedInboxObject = x.sharedInbox ?? (x.endpoints ? x.endpoints.sharedInbox : undefined);
@@ -168,16 +170,16 @@ export class ApPersonService implements OnModuleInit {
 				const collectionUri = getApId(xCollection);
 				if (typeof collectionUri === 'string' && collectionUri.length > 0) {
 					if (this.utilityService.punyHost(collectionUri) !== expectHost) {
-						throw new Error(`invalid Actor: ${collection} has different host`);
+						throw new UnrecoverableError(`invalid Actor - ${collection} has different host: ${uri}`);
 					}
 				} else if (collectionUri != null) {
-					throw new Error(`invalid Actor: wrong ${collection}`);
+					throw new UnrecoverableError(`invalid Actor: wrong ${collection} in ${uri}`);
 				}
 			}
 		}
 
 		if (!(typeof x.preferredUsername === 'string' && x.preferredUsername.length > 0 && x.preferredUsername.length <= 128 && /^\w([\w-.]*\w)?$/.test(x.preferredUsername))) {
-			throw new Error('invalid Actor: wrong username');
+			throw new UnrecoverableError(`invalid Actor - wrong username: ${uri}`);
 		}
 
 		// These fields are only informational, and some AP software allows these
@@ -185,7 +187,7 @@ export class ApPersonService implements OnModuleInit {
 		// we can at least see these users and their activities.
 		if (x.name) {
 			if (!(typeof x.name === 'string' && x.name.length > 0)) {
-				throw new Error('invalid Actor: wrong name');
+				throw new UnrecoverableError(`invalid Actor - wrong name: ${uri}`);
 			}
 			x.name = truncate(x.name, nameLength);
 		} else if (x.name === '') {
@@ -194,24 +196,24 @@ export class ApPersonService implements OnModuleInit {
 		}
 		if (x.summary) {
 			if (!(typeof x.summary === 'string' && x.summary.length > 0)) {
-				throw new Error('invalid Actor: wrong summary');
+				throw new UnrecoverableError(`invalid Actor - wrong summary: ${uri}`);
 			}
 			x.summary = truncate(x.summary, summaryLength);
 		}
 
 		const idHost = this.utilityService.punyHost(x.id);
 		if (idHost !== expectHost) {
-			throw new Error('invalid Actor: id has different host');
+			throw new UnrecoverableError(`invalid Actor - id has different host: ${uri}`);
 		}
 
 		if (x.publicKey) {
 			if (typeof x.publicKey.id !== 'string') {
-				throw new Error('invalid Actor: publicKey.id is not a string');
+				throw new UnrecoverableError(`invalid Actor - publicKey.id is not a string: ${uri}`);
 			}
 
 			const publicKeyIdHost = this.utilityService.punyHost(x.publicKey.id);
 			if (publicKeyIdHost !== expectHost) {
-				throw new Error('invalid Actor: publicKey.id has different host');
+				throw new UnrecoverableError(`invalid Actor - publicKey.id has different host: ${uri}`);
 			}
 		}
 
@@ -298,18 +300,18 @@ export class ApPersonService implements OnModuleInit {
 	 */
 	@bindThis
 	public async createPerson(uri: string, resolver?: Resolver): Promise<MiRemoteUser> {
-		if (typeof uri !== 'string') throw new Error('uri is not string');
+		if (typeof uri !== 'string') throw new UnrecoverableError(`uri is not string: ${uri}`);
 
 		const host = this.utilityService.punyHost(uri);
 		if (host === this.utilityService.toPuny(this.config.host)) {
-			throw new StatusError('cannot resolve local user', 400, 'cannot resolve local user');
+			throw new StatusError(`cannot resolve local user: ${uri}`, 400, 'cannot resolve local user');
 		}
 
 		// eslint-disable-next-line no-param-reassign
 		if (resolver == null) resolver = this.apResolverService.createResolver();
 
 		const object = await resolver.resolve(uri);
-		if (object.id == null) throw new Error('invalid object.id: ' + object.id);
+		if (object.id == null) throw new UnrecoverableError(`null object.id: ${uri}`);
 
 		const person = this.validateActor(object, uri);
 
@@ -341,16 +343,16 @@ export class ApPersonService implements OnModuleInit {
 		const url = getOneApHrefNullable(person.url);
 
 		if (person.id == null) {
-			throw new Error('Refusing to create person without id');
+			throw new UnrecoverableError(`Refusing to create person without id: ${uri}`);
 		}
 
 		if (url != null) {
 			if (!checkHttps(url)) {
-				throw new Error('unexpected schema of person url: ' + url);
+				throw new UnrecoverableError(`unexpected schema of person url ${url}: ${uri}`);
 			}
 
 			if (this.utilityService.punyHost(url) !== this.utilityService.punyHost(person.id)) {
-				throw new Error(`person url <> uri host mismatch: ${url} <> ${person.id}`);
+				throw new UnrecoverableError(`person url <> uri host mismatch: ${url} <> ${person.id}`);
 			}
 		}
 
@@ -441,7 +443,7 @@ export class ApPersonService implements OnModuleInit {
 			if (isDuplicateKeyValueError(e)) {
 				// /users/@a => /users/:id のように入力がaliasなときにエラーになることがあるのを対応
 				const u = await this.usersRepository.findOneBy({ uri: person.id });
-				if (u == null) throw new Error('already registered');
+				if (u == null) throw new UnrecoverableError(`already registered a user with conflicting data: ${uri}`);
 
 				user = u as MiRemoteUser;
 			} else {
@@ -450,7 +452,7 @@ export class ApPersonService implements OnModuleInit {
 			}
 		}
 
-		if (user == null) throw new Error('failed to create user: user is null');
+		if (user == null) throw new Error(`failed to create user - user is null: ${uri}`);
 
 		// Register to the cache
 		this.cacheService.uriPersonCache.set(user.uri, user);
@@ -501,7 +503,7 @@ export class ApPersonService implements OnModuleInit {
 	 */
 	@bindThis
 	public async updatePerson(uri: string, resolver?: Resolver | null, hint?: IObject, movePreventUris: string[] = []): Promise<string | void> {
-		if (typeof uri !== 'string') throw new Error('uri is not string');
+		if (typeof uri !== 'string') throw new UnrecoverableError('uri is not string');
 
 		// URIがこのサーバーを指しているならスキップ
 		if (this.utilityService.isUriLocal(uri)) return;
@@ -554,16 +556,16 @@ export class ApPersonService implements OnModuleInit {
 		const url = getOneApHrefNullable(person.url);
 
 		if (person.id == null) {
-			throw new Error('Refusing to update person without id');
+			throw new UnrecoverableError(`Refusing to update person without id: ${uri}`);
 		}
 
 		if (url != null) {
 			if (!checkHttps(url)) {
-				throw new Error('unexpected schema of person url: ' + url);
+				throw new UnrecoverableError(`unexpected schema of person url ${url}: ${uri}`);
 			}
 
 			if (this.utilityService.punyHost(url) !== this.utilityService.punyHost(person.id)) {
-				throw new Error(`person url <> uri host mismatch: ${url} <> ${person.id}`);
+				throw new UnrecoverableError(`person url <> uri host mismatch: ${url} <> ${person.id}`);
 			}
 		}
 
@@ -721,8 +723,16 @@ export class ApPersonService implements OnModuleInit {
 		const _resolver = resolver ?? this.apResolverService.createResolver();
 
 		// Resolve to (Ordered)Collection Object
-		const collection = await _resolver.resolveCollection(user.featured);
-		if (!isCollectionOrOrderedCollection(collection)) throw new Error('Object is not Collection or OrderedCollection');
+		const collection = await _resolver.resolveCollection(user.featured).catch(err => {
+			if (err instanceof AbortError || err instanceof StatusError) {
+				this.logger.warn(`Failed to update featured notes: ${err.name}: ${err.message}`);
+			} else {
+				this.logger.error('Failed to update featured notes:', err);
+			}
+		});
+		if (!collection) return;
+
+		if (!isCollectionOrOrderedCollection(collection)) throw new UnrecoverableError(`featured ${user.featured} is not Collection or OrderedCollection: ${user.uri}`);
 
 		// Resolve to Object(may be Note) arrays
 		const unresolvedItems = isCollection(collection) ? collection.items : collection.orderedItems;
diff --git a/packages/backend/src/core/activitypub/models/ApQuestionService.ts b/packages/backend/src/core/activitypub/models/ApQuestionService.ts
index a2cdaf02c..1a4299858 100644
--- a/packages/backend/src/core/activitypub/models/ApQuestionService.ts
+++ b/packages/backend/src/core/activitypub/models/ApQuestionService.ts
@@ -4,6 +4,7 @@
  */
 
 import { Inject, Injectable } from '@nestjs/common';
+import { UnrecoverableError } from 'bullmq';
 import { DI } from '@/di-symbols.js';
 import type { UsersRepository, NotesRepository, PollsRepository } from '@/models/_.js';
 import type { Config } from '@/config.js';
@@ -11,8 +12,8 @@ import type { IPoll } from '@/models/Poll.js';
 import type { MiRemoteUser } from '@/models/User.js';
 import type Logger from '@/logger.js';
 import { bindThis } from '@/decorators.js';
-import { getOneApId, isQuestion } from '../type.js';
 import { UtilityService } from '@/core/UtilityService.js';
+import { getApId, getApType, getOneApId, isQuestion } from '../type.js';
 import { ApLoggerService } from '../ApLoggerService.js';
 import { ApResolverService } from '../ApResolverService.js';
 import type { Resolver } from '../ApResolverService.js';
@@ -48,10 +49,10 @@ export class ApQuestionService {
 		if (resolver == null) resolver = this.apResolverService.createResolver();
 
 		const question = await resolver.resolve(source);
-		if (!isQuestion(question)) throw new Error('invalid type');
+		if (!isQuestion(question)) throw new UnrecoverableError(`invalid type ${getApType(question)}: ${getApId(source)}`);
 
 		const multiple = question.oneOf === undefined;
-		if (multiple && question.anyOf === undefined) throw new Error('invalid question');
+		if (multiple && question.anyOf === undefined) throw new Error(`invalid question - neither oneOf nor anyOf is defined: ${getApId(source)}`);
 
 		const expiresAt = question.endTime ? new Date(question.endTime) : question.closed ? new Date(question.closed) : null;
 
@@ -72,21 +73,20 @@ export class ApQuestionService {
 	 */
 	@bindThis
 	public async updateQuestion(value: string | IObject, actor?: MiRemoteUser, resolver?: Resolver): Promise<boolean> {
-		const uri = typeof value === 'string' ? value : value.id;
-		if (uri == null) throw new Error('uri is null');
+		const uri = getApId(value);
 
 		// URIがこのサーバーを指しているならスキップ
-		if (this.utilityService.isUriLocal(uri)) throw new Error('uri points local');
+		if (this.utilityService.isUriLocal(uri)) throw new Error(`uri points local: ${uri}`);
 
 		//#region このサーバーに既に登録されているか
 		const note = await this.notesRepository.findOneBy({ uri });
-		if (note == null) throw new Error('Question is not registered');
+		if (note == null) throw new Error(`Question is not registered (no note): ${uri}`);
 
 		const poll = await this.pollsRepository.findOneBy({ noteId: note.id });
-		if (poll == null) throw new Error('Question is not registered');
+		if (poll == null) throw new Error(`Question is not registered (no poll): ${uri}`);
 
 		const user = await this.usersRepository.findOneBy({ id: poll.userId });
-		if (user == null) throw new Error('Question is not registered');
+		if (user == null) throw new Error(`Question is not registered (no user): ${uri}`);
 		//#endregion
 
 		// resolve new Question object
@@ -95,25 +95,25 @@ export class ApQuestionService {
 		const question = await resolver.resolve(value);
 		this.logger.debug(`fetched question: ${JSON.stringify(question, null, 2)}`);
 
-		if (!isQuestion(question)) throw new Error('object is not a Question');
+		if (!isQuestion(question)) throw new UnrecoverableError(`object ${getApType(question)} is not a Question: ${uri}`);
 
 		const attribution = (question.attributedTo) ? getOneApId(question.attributedTo) : user.uri;
 		const attributionMatchesExisting = attribution === user.uri;
 		const actorMatchesAttribution = (actor) ? attribution === actor.uri : true;
 
 		if (!attributionMatchesExisting || !actorMatchesAttribution) {
-			throw new Error('Refusing to ingest update for poll by different user');
+			throw new UnrecoverableError(`Refusing to ingest update for poll by different user: ${uri}`);
 		}
 
 		const apChoices = question.oneOf ?? question.anyOf;
-		if (apChoices == null) throw new Error('invalid apChoices: ' + apChoices);
+		if (apChoices == null) throw new UnrecoverableError(`poll has no choices: ${uri}`);
 
 		let changed = false;
 
 		for (const choice of poll.choices) {
 			const oldCount = poll.votes[poll.choices.indexOf(choice)];
 			const newCount = apChoices.filter(ap => ap.name === choice).at(0)?.replies?.totalItems;
-			if (newCount == null || !(Number.isInteger(newCount) && newCount >= 0)) throw new Error('invalid newCount: ' + newCount);
+			if (newCount == null || !(Number.isInteger(newCount) && newCount >= 0)) throw new UnrecoverableError(`invalid newCount: ${newCount} in ${uri}`);
 
 			if (oldCount !== newCount) {
 				changed = true;
diff --git a/packages/backend/src/core/activitypub/type.ts b/packages/backend/src/core/activitypub/type.ts
index 6b1a82ea5..7918032d8 100644
--- a/packages/backend/src/core/activitypub/type.ts
+++ b/packages/backend/src/core/activitypub/type.ts
@@ -3,6 +3,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
+import { UnrecoverableError } from 'bullmq';
 import { fromTuple } from '@/misc/from-tuple.js';
 
 export type Obj = { [x: string]: any };
@@ -68,7 +69,7 @@ export function getApId(value: string | IObject | [string | IObject]): string {
 
 	if (typeof value === 'string') return value;
 	if (typeof value.id === 'string') return value.id;
-	throw new Error('cannot determine id');
+	throw new UnrecoverableError('cannot determine id');
 }
 
 /**