Thanks to your response
If I add an AD user to a group in commvault, who got the right to install software (agents) to a client witch isn't present within the commcell at this time, this user can login via the java tool or the Command Center and add a new machine, he wants to backup.
During the installation, the new server will be registed at commcell.
And as I said before, the installation of the commvault agent by using a test user who uses the command center is working fine. The only Problem is, that after the installation is complete, the server with the installed agent disappiers for the test user, and I as Admin need to tell the new server manually who it's owner is.
I thought if someone pushes an agent, than that user will be considered as owner.