LM, it’s a very very very bad combination.
Sooner or later you will have trouble: in Windows Registry, in residents…
Forget about having NAV and avast! in the same computer. I used NAV in the past and changed completely to avast! (after loosing a lot of time to get rid of trash left behind from Symantec :(). So, I see no advantage to have NAV resident disabled and avast! as on-access scanner. At most, you can do the contrary. I know that NAV as resident will hogh the computer but, it’s the less bad thing you can do.

My suggestion: don’t try to have both in the same system, specially XP SP2 :stuck_out_tongue: