Norton Antivirus keeps disabling

[fustercluck]

I've had Norton Antivirus 2005 installed for a while, but recently after i upgraded it started disabing itself, seems to be almost random. Sometimes i can just click enable and it will work again, usually not though, instead it usually gives me some generic error like "Norton has encountered an internal program error" . Not sure what's causing it, it worked before fine for a long time. It's not expired or anything.