zotero sync fails 429 too many authentication failures

kcrowston · 2026-10-04T20:52:31+00:00

My Zotero sync has stopped working. In the log, I see 429 too many authentication failures. Will that resolve itself after sometime or do I need to do something proactively to fix my account? Perhaps relatedly, I get a server error when I try to create or edit an API key.

kcrowston · 2026-10-04T21:15:02+00:00

It's iOS Debug Log: D2146587701 if that is helpful. I get the same error on my laptop. But I can log in to the website, though it's a bit flaky.

kcrowston · 2026-10-05T12:44:14+00:00

Apparently waiting works because it synced successfully this morning.

kcrowston · 2026-10-05T15:49:28+00:00

To fix the iPad sync, I logged out of the iPad, deleted its API key, then logged back in and it synced right away.

dstillman · 2026-10-05T16:31:54+00:00

It looks like this was due to the application key being deleted — presumably in your account settings — while the app was open. There's a bug that caused the app to not properly notice that its key was no valid and continue to make requests, which led to your getting locked out. We'll fix that, but logging out and in again was the correct fix.

kcrowston · 2026-10-05T17:14:38+00:00

Thanks for the comment. Actually, I was having sync problems on both my laptop and my iPad. Turning off Zotero's automatic sync and letting it sit overnight fixed the laptop. For the iPad, just logging out and back in didn't work by itself; it was still not syncing. What finally worked was logging out, deleting the application key and then logging back in. So maybe the iPad got its key wrong somehow and then the frequent authentication failures locked the account? It must have been something like that because yesterday I couldn't do anything with the access keys and today I can again.

dstillman · 2026-10-05T17:24:30+00:00

The Debug ID you provided was the app trying a key that you deleted. If you were rate-limited before that for some reason, you would have been locked out on all devices for a period of time, but this was a permanent condition based on the deleted key. If you run into a problem in the future, report it before making any changes and we can investigate.