Thanks for reply ,
My bind credentials are ok because when I use ldp.exe i can bind this user and view this OU. (I copied DN from active directory)
This is very strange problem. I've looked through the whole forum and documentation and can not find a solution.
I implemented moodle on other domains and there was no problem with the LDAP connection. This domain has a lot domain objects - about 1000 - maybe this is a problem)
thanks a lot for help