backup exec 9.1. Dissapears. Curse?

Hi,
I have a client with several offices; each one is a site with a domain controller.
Veritas is working fine in the main office. When I tried to install in the rest of the offices I have found several problems, in some of the offices the installation stops at some point and then start uninstalling. In other offices the installation goes fine and veritas even works for a couple of days and then stop working, the veritas services cant be restarted because the systems says that service have been marked for deletion, I have also found in some of the servers were I was able to install it that after a few days veritas software was totally gone, disappear, finito :(

Have anybody had a similar experience?

Thanks