I checked the log files and it shows -> No UserObject! at /opt/otrs//Kernel/System/Auth/LDAP.pm line 25.\n
Then I found on Otterhub the same error, but it didn't helped. The solution posted the user "crythias" and it didn't worked ->
bad: $Self->{'Customer::AuthModule'} = 'Kernel::System::Auth::LDAP';
good: $Self->{'Customer::AuthModule'} = 'Kernel::System::CustomerAuth::LDAP';
<-
I tried this but without luck

Can someone help me?
PS: I am new to CentOS and OTRS.