After going to 4.1,1 or 3.10.7 some users can't login anymore
From Joomla! Documentation
Revision as of 10:56, 30 March 2022 by Bembelimen (Add additional note)
Some users can't login after they have been able to login without entering a PW right after the update to 4.1.1 or 3.10.7.
This pertains only to Joomla! version(s): 4.1.1 & 3.10.7
What is the cause
After the update the Joomla Core binds the user on login to the authentication provider. But when your first login is with an none primary update provider like the Cookie (Remember Me) after logging out the user can login again.
How to fix
When you still have a SuperUser who can login into the backend, please go to: Users -> Manage -> "Username" -> Authentication Method -> Set to "None"
When you don't have a Super User who can login into the backend please go to the #__users table for the user and clear the value that's set in the "authProvider" column.
Now make an update to 3.10.8 or 4.1.2 or higher to apply the fix on all affected users and protect against the issue in the first place.