I HAD Norton Internet Security until I installed Tiger. It wouldn't let Norton Ant-Virus, Firewall or Internet Privacy work at all. I tried re-installing and updating four times before I gave up. I then joined .Mac so I could get the Virex software (ex-PC, bit nervous about no protection). Guess what? That doesn't work either. I have noticed on the .Mac site that it does now say "Panther only" next to Virex. It also says that next to StickyBrain (the other thing I wanted) although my trial version seems to still work OK. So, NO ANTI-VIRUS SOFTWARE. Anybody know anything that works (so I can blow another £70 to be where I was before Tiger).