A quick scan with Malwarebytes weekly, and a full scan with avast!, monthly.
With avast! almost never (I find it totally useless), but with MBAM and ESET online about twice a month.
Full Scan-Once a week ;D 8)
25 boot time scans a day is the minimum.
Usually I also run 55 full scans and 379 quick scans.
Everyone should do this daily. 
;D
I do this in 23457687657645637465 computers daily, one by one ;D
:o :o
Good. 
Thx for all of you replying
anyway is anyone here who needs also charts
I can make Pie Charts, Bar Charts, Doughnut Charts
Whatever you want
Anyway
A scan is an action taken by a specific program to check if the computer or his files are infected with malware
also known as virusses. There are several methods which a scanning software can use to identify malware:
Signature-based detection
Traditionally, antivirus software heavily relied upon signatures to identify malware. This can be very effective, but cannot defend against malware unless samples have already been obtained and signatures created. Because of this, signature-based approaches are not effective against new, unknown viruses.
As new viruses are being created each day, the signature-based detection approach requires frequent updates of the virus signature dictionary. To assist the antivirus software companies, the software may allow the user to upload new viruses or variants to the company, allowing the virus to be analyzed and the signature added to the dictionary.
Although the signature-based approach can effectively contain virus outbreaks, virus authors have tried to stay a step ahead of such software by writing “oligomorphic”, “polymorphic” and, more recently, “metamorphic” viruses, which encrypt parts of themselves or otherwise modify themselves as a method of disguise, so as to not match virus signatures in the dictionary.
Heuristics
Some more sophisticated antivirus software uses heuristic analysis to identify new malware or variants of known malware.
Many viruses start as a single infection and through either mutation or refinements by other attackers, can grow into dozens of slightly different strains, called variants. Generic detection refers to the detection and removal of multiple threats using a single virus definition.
For example, the Vundo trojan has several family members, depending on the antivirus vendor’s classification. Symantec classifies members of the Vundo family into two distinct categories, Trojan.Vundo and Trojan.Vundo.B.
While it may be advantageous to identify a specific virus, it can be quicker to detect a virus family through a generic signature or through an inexact match to an existing signature. Virus researchers find common areas that all viruses in a family share uniquely and can thus create a single generic signature. These signatures often contain non-contiguous code, using wildcard characters where differences lie. These wildcards allow the scanner to detect viruses even if they are padded with extra, meaningless code. A detection that uses this method is said to be “heuristic detection.”
I love Doughnuts
On my main computer, full scan at 8 P.M. on Friday.
Never found anything.
On the other computers, just once in a while.
Tech,
We have discussed this before.
http://forum.avast.com/index.php?topic=74170.msg626409#msg626409
Read replies 151 thru 156.
Thanks rdmaloyjr, respect your point of view.
Sorry, but I don’t share it
Me neither, MSE was a failure here.
MSE works for me, use whatever works for you.
If the problem with avast! and Opera gets fixed, I might go back to avast!.
How many times has your hard drive burned out with this many scans? ;D ???
Usually I scan once a week(In Fridays).
Never, I change the HD daily. ;D
I use underwear HDs and also change them daily ;D
Scan only when I feel the needs.
MSE is nice but it still eat more resource than Avast and Avira do. Avast better than Avira in resource usage and feature. So, it’s Avast for me.
I’m using Opera and having no problem with it. Web shield scan anything that I download using Opera. What kind of problem that you have by using Avast in your machine?
I used to do daily quick scan then realised that was just not necessary. Now, i do a weekly quick scan and a monthly full scan.