Same issue, was playing no problem yesterday, closed the game, came back today and now I can't log in on any platform. Server page says fully operational and I was watching someone stream it earlier so it has to be either an account problem or a specific issue with a single server I would imagine. Super annoying.

grr

Mine is doing similar Unable to login "Failed deserialization...."

急にログインが出来なくなりました。パスワード編集画面で再設定を行う途中でコードを聞かれましたがコードを知りません。

I have uninstalled and reinstalled it 2 times and the error persists.

Since October, the frequency of these error messages has increased. Repeatedly logging in and out doesn't help. Please respond as soon as possible.

Having this issue right now as well - can't get in on any platform.

Having this issue right now.

same

Ssme thing since update. Cool that in this update was "Fixed a bug that could block logging in with a spurious "Authentication Failed" and/or "Attach Failed" message"...

Help please. PLease compensate my gold T_T

This issue started today after latest update.

RECEIVING THIS MESSAGE EACH TIME I TRY TO LOGIN..

I had this problem starting late last week. Previous times I saw the issue have usually been due to the server being down, and fixed simply by waiting less than a day. This time was different, and I and an acquaintance tried half a dozen devices over 5 days. Those with Windows 10 failed every time, including after trying every troubleshooting option suggested by Wizards Support. All devices with other OS were fine.

Our eventual solution: use prior version of the Arena launcher, which can be found in older versions of the installer (we used one from 2020 that had been saved way back then). We ended up downloading a 5GB update, and it had a few other issues, but it played perfectly.

Authentication failed for (username)
Timeout 14-1 -2022

Unable to log in. Authentication failed for account: time-out.

Mine has been like this since Dec 30th! When is wizards going to finally care?!

I got this for the last 4 days now.

Cannot start from this morning using my iPad. Is there any solution known?

4 days of this. tried everything