What are you referring to? The game version? The DLC? Are you trying to reinstall the game? Perhaps the update you're thinking of is already in your Xbox's cache.
Wait, you mean general game glitches? Is that what you mean by "bugs"? This is a Bethesda game man. Bugs are part of the package.
Anyway I don't know. I find it hard to believe you have a virus on your Xbox - it could simply be a corrupt hard drive. But maybe you triggered some kind of authentication error; my only real recommendation is to try re-installing it under a different profile.
If that doesn't work I guess you could just format the drive.
Edit: Oh and try re-installing the actual game as well, if you haven't already done that.
Good luck. Let me know how it's going in a couple of weeks.