HellO!
I installed OsClass on cPanel and I moved a few days ago on ISPManager, and i receive this errors.


Warning: session_start(): The session id is too long or contains illegal characters, valid characters are a-z, A-Z, 0-9 and '-,' in /var/www/ofertez/data/www/ofertez.ro/oc-includes/osclass/core/Session.php on line 57

Warning: session_start(): Failed to read session data: files (path: /var/www/ofertez/data/bin-tmp/) in /var/www/ofertez/data/www/ofertez.ro/oc-includes/osclass/core/Session.php on line 57

Warning: session_regenerate_id(): Cannot regenerate session id - session is not active in /var/www/ofertez/data/www/ofertez.ro/oc-includes/osclass/core/Session.php on line 58

Who can helps me? Thanks!

That sounds like hosting issue.
Reinatall osclass, check with hosting and if they refuse to help (that it is script issue...) then.... Run away and pick better hosting, it does not make sense to waste your time.