Colorado 14GB Internal tape drive dosn't repond when start backup job

[Lily Ma]

I use Backup Exec 7.0, when I start job, nothing happened, following trouble shoot, I found the service qic 517 was not started, I tried to start, got error msg: service is disabled and can not be started. I checked hardware profile for qic 517, there is no profile.
I tried to start from Windows NT native backup program, I got error msg: the device is detected and driver is installed, but tape drive didn't respond.
The only thing I noticed is that first I installed Backup Exec, it worked, then I tried to install ARCserve 6.5 in same server machine, installation was not success, service can not be start, so I disabled the ARCserve dabase engine and related services from Control Panal/Services, then uninstalled Backup Exec and Reinstalled Backup Exec, but still not working.
Please advise.