Why Automatic Antivirus Scans are
Do you regularly open your Antivirus Software and run scans? Microsoft Security Essentials and other
antivirus programs believe it is necessary, warning you that your computer may be at risk if you haven't
done it in a while.
In reality, these manual scans are not all that they seem. You can usually ignore your antivirus and it
will do its work in the background without your help, alerting you only when it encounters a problem.
Why manual virus scans are unnecessary
Your antivirus always runs in the background. It monitors the processes running on your system,
ensuring that no malicious processes are running. Whenever you download a new file or open a
program, your antivirus quickly intervenes, examines the file, and compares it to viruses before allowing
it to run. If you download a virus, your antivirus will notice it without the need to scan anything. For
example, try downloading the EICAR test file - your antivirus will spring into action and take care of
the file without the need for manual scans.
This feature is generally known as background scanning, real-time protection, resident protection, on-
demand scanning, or something like that.
In other words, you don't need to run manual scans because your antivirus has already checked all files
for malware as it arrives. You are also aware of all the software that is running on your system. Your
antivirus program doesn't need you to click a button; it's already doing the job.
Anyway, your antivirus probably already runs its own manual scans. Antiviruses generally run
background system scans once a week without interrupting you.
The Microsoft Security Essentials message is particularly silly. If MSE really believes that a manual
scan is necessary, MSE has the ability to perform the scan in the background rather than scaring its
users into clicking a button.
When to run manual scans
Manual scans are still useful in some cases, but you don't need to regularly open your antivirus program