application unable to install - error 105

I am trying to install an application on a W2K3 server. It starts working and then it stalls - no error message. But the app name still shows in the Task Manager - processes. It is not clocking time or resources. I have tried turning off the on-access scan. I have checked permissions - I am doing this as an domain/administrator with full permissions. When closing the process I see:
"Setup is unable to run a program needed to proceed with the installation. Restart your system and try again. Error 105."