Recent activity just prior to the onset of the reboots - I installed Symantec Antivirus for Server 9.0 on our server, and deployed it to this particular machine. When I went to this machine to check on it, it gave an error in loading/starting the program so I went to reboot. Then the rebooting automatically began. I ran the latest NAV update and scanned the system prior to installation.
I've tried booting up in Safe Mode and all it does is freeze the machine. I can't seem to get into the OS at all.