This problem is on my server - temporary - since month ... it does not matter which settings are in config.php .....
On my server I have hundreds of loggins each day, without any problem.
Once/twice a week it happens suddenly, no error just fall back to login.
If we try a wrong userid or password, it is recognised as wrong login, server reaction is ok ..
Than we try these possibilities:
- Sometimes user can login in, calling once
reload the session-test.php twice, because first we get the message "NO Session found" and then start moodle again, most of the time it works ... - OR: closing the browser, may help ...
- OR: sometimes it takes 15 min to 30 min time to wait and doing nothing and error will leave, works - if you have time.
My provider and me, we have NO idea what maybe the reason. ...
Peter