I just did a update on my BitDefender Pro 9 on my PC and I noticed that the update was quite a big one, normally bigger than the normal virus definition updates. Now after the updates were finished I was asked to re-boot my PC. I've this same thing a while back, though very rare I'm asked to re-boot the PC. Whats the reason behind this for me to have to re-boot the computer. Would it also be a program update as well or just purely the antivirus definitions update. Assume it was also a prog update, after I re-booted the PC and had a look at BD Pro 9, the prog still looked very much the same and could not seem to see any changes.