I am using Avast! Internet Security. Today I face a Problem of virus detection.
Under normal conditions, I right-click “scan”(on the top of the file) . It(avast) can not detect the virus which is called “免杀asp木马.asa”. I scan it after unzipping it.
But I put "免杀asp木马.asa " unzipped, added to the “Virus Chest”, right-click “scan”, avast can detect it as(Win32: Ace-j [Trj]).
Why [Avast! Internet Security] cannot detect the virus via normal conditions?
Here is the file of virus. The password of the file is 123.
Enable “Scan all files” under “File System Shield”. Both Scan on opening and scan on writing. This will force avast! to scan all files, even those that are harmless based on extension itself. You can try this to see if it will then be detected. But i recommend you disable this after you test because doing so will make avast! slightly slower (but also slightly more secure).