diff --git a/packages/lib/SyncTargetJoplinCloud.ts b/packages/lib/SyncTargetJoplinCloud.ts
index 1b40ec7bddc..a4dd4be17c5 100644
--- a/packages/lib/SyncTargetJoplinCloud.ts
+++ b/packages/lib/SyncTargetJoplinCloud.ts
@@ -56,7 +56,7 @@ export default class SyncTargetJoplinCloud extends BaseSyncTarget {
 			const sessionId = await api.sessionId();
 			return !!sessionId;
 		} catch (error) {
-			if (error.code === 403) {
+			if ([403, 404].includes(error.code)) {
 				return false;
 			}
 			throw error;
diff --git a/packages/lib/Synchronizer.ts b/packages/lib/Synchronizer.ts
index 56b98baa0b0..d8650fdad01 100644
--- a/packages/lib/Synchronizer.ts
+++ b/packages/lib/Synchronizer.ts
@@ -524,7 +524,7 @@ export default class Synchronizer {
 					// await uploadSyncInfo(this.api(), remoteInfo);
 				}
 			} catch (error) {
-				if (error.code === 403) {
+				if ([403, 404].includes(error.code)) {
 					this.dispatch({ type: 'MUST_AUTHENTICATE', value: true });
 				}
 				if (error.code === 'outdatedSyncTarget') {