How do I reset my IMAP password?
If you setup your IMAP account using the default OAuth via the automatic email wizard then you just change your password in your mail account online and then eM Client will automatically then pickup the new password.
However if you manually setup your IMAP account via" Add / Mail / Other " that you would then have to change your password online in your mailbox and in eM Client via “Menu / Accounts” under the IMAP tab.
Tried this but no change.
I would then contact your IMAP mailbox technical support for assistance with your password.
Could be your mailbox provider has changed something their end and maybe now requires an eg: “App password” for mail clients and not your normal IMAP password.