How often should I scan my computer?

To be honest, I very rarely scan, and I am online nearly every moment outside of sleep/work. You can get by doing it that way if you are safe as far as actual preventative measures. Use a secure browser, watch your downloads (Only use files you KNOW are safe), and use both a good firewall, and router-based security. People seem to underestimate the power of a router-based firewall. I don't really trust most scanners nowadays due to the insane amount of false positives that come up due to so many small things that can contribute to something being flagged as evil. If you are not technologically savvy, though, I would still suggest regular scanning, but for the most part, if you still manage to catch something, even after following the above rules, then you've almost definitely done it to yourself.

System scan(scandisk and defragment) once a week; virus scanning, i recommend do it daily...

It is good practice to scan the computer at least once a week, so that if a problem occurs then it will not be left ignored for months. I understand your problem because we all tend to use the computer immediately and have little time for maintenance, which is why you should automate the process. You can set a schedule for scanning the computer at a certain time every week, and I would suggest choosing a time when you are usually asleep. This option can be set either via your anti virus program or by going to "scheduled tasks" which you can access through the Control Panel.

I think every week is good for scanning for viruses and spyware. And try to update them every day if possible (or use autoupdate). If your computer finds over 10 (seperate) baddies, I think you should look into scanning more often. But if you do set up your system to autoscan, make sure you leave it on, it won't run any if it's off :) (I thought it would still run them when I first started setting them up lol) If you want program suggestions, there are many free ones that are good. Spybot and Adaware are most reccommended for spyware removal. SpywareBlaster is good for preventing some spywares from getting into your system. Many people will advise you to use AVG for your antivirus, but I personally prefer Avira, I seem to be getting less viruses on my system with it. Also, before you run the scans, you should either do DiskCleanup or get Ccleaner and run that (the two C's is not a mistype). OH! And there are two highly reccommended online virus scans, PandaSoftware and TrendMicro. I don't think you need to use the online ones more than once a month, or if you think your virus scanner isn't catching a virus on your system though. I do use a few more thingys, but I think I might be overboard with them lol.

Keeping a healthy computer includes frequent AV scanning but before you do this, be sure to keep your AV updated and always have an antispyware program. Also keep system backups if possible.

i use to scan onces in a month .i refer that use antivirus updation requrally .put in automatic scan with antivirus.it will do at back end

I do a full scan about once a week. my virus check spyware check is done on access which is the reason I do a full scan once a week. I have it scheduled to run in the middle of the night. so it doesnt interfere with what I do durring the day

if you have a good anti virus installed in the system then it is not necessary or needed to scan your computer that ofter as any process which behaves or tries to access the internet are autometically scanned by the antivirus.

i usually scan once a week for adware and spyware and my antivirus automatically checks each day. i run the adware and spyware more often if my system seems slow.

Scan for viruses? it depends.. my suggestion is if you have time you just scan it.. everyother day if possible.

Firstly, most anti-virus and anti-spyware scanners come with the automatic scanning feature which means that u don't have to worry about scanning it at all! secondly, what kind of a user are u? If ur kinda experienced and know wat's good and bad u should probably turn off ur automatic scans and do it urself once a fortnight or something. However if u don't know where the attacks come from use AVG it has a pretty good automatic scan feature - blocks viruses as they come in! By the way whatever u use don't forget to keep it updated.