Norton Ghost 15 Service Fails

Hi, I'm having a problem with a copy of Norton Ghost 15 I purchased recently.

 

Yesterday, I installed it and was able to make a backup normally. Norton Ghost seemed to work fine today, but then I noticed in the system tray that Ghost had a red line through it. When hovering my mouse over the tray icon, it says "unable to retrieve information from the agent: Access denied".

 

I then decided to check out if the Norton Ghost service was running. Its not. Its set to automatic. I try starting it, it starts successfully, but in a second it shuts off again.

 

Any idea why?

 

Info about my PC:

OS: Windows 7 Ultimate x64

Security: Avira AntiVir Personal, ThreatFire, ZoneAlarm. UAC is off.

Logged into administrator.

 

Thanks in advance for your help.