I do a virus scan whenever I feel like doing one so it could be every few days or it could be months apart before I do one but i keep avast updated. But I do spyware scans almost everyday.
I run continuous scans, scans pretty much all outgoing and incoming processes and data over the net. As far as straight virus scans, only when something is suspected, otherwise it is always caught when downloaded or ran.
My computer is set up to scan itself once a month. Does it automatically for me in the background, and I've had no problems yet, so I don't worry so much.
When I had Norton AV, it was set to auto-scan every day. Never caught a thing. Now that I use Avast which is also kept up to date automatically, I scan everything manually once a week or so.
never ran a scan , since NOD32 has proactive defense / scanning, i don't set a sechdele, i set everything in sight to DELETE, but since saturday i learned a huge lesson im gonna run it weekly or every 3 days
Normally I never do virus scans. I just got Kaspersky because I really like the trail. It found 1 trojan in all the files I've collected over the ~ 1 year that I've had this computer.