I guess this was in case of a failure with the cache.
The steps i did.
delete cache
rebuild config
set permissions
Now I have the login screen but can´t login. I didn´t change anything in the config.pm. LDAP Login is activated.
I can´t find any failure in the log of apache and syslog.

When i want to press the Login button, nothing happens.
Has anyone an idea what i can do to solve it?