Keylogger That's not Identified by Scans

[Okashira]

I know I've read mention of a keylogger that's not identified by regular scans, and after a friend's account was hacked I was trying to find what it was exactly so he could look in his active processes and make sure it's not running, but I can't find any mention of it. Does anyone know of it? Or has it been fixed so it *is* identified by scans?

[Nixia]

There isn't *one* virus that is undetectable by anti-virus programs. There are billions of different viruses and some of them disguise themselves so they won't be detected by anti-virus programs. I would be very surprised if there was a anti-virus program that detected every single virus ever made.
There are many good and free AV programs that you could try but I recommend you to delete your current one before installing the other. Two anti-virus programs on the same computer might cause problems.

Good free anti-virus programs:
Avast
Avg
Kaspersky

*All of these programs are trial versions which means you can use them for free for about 30 days. If you want to continue getting updates after the 30 days then you'll have to pay*

[Cilraaz]

Add Avira to the anti-virus list and MalwareBytes to the anti-malware list.

Also, heuristic scanning is improving how anti-virus works. A lot of anti-virus programs are now searching for specific actions (replacing system files, deleting system files, logging keystrokes, etc) rather than specific bits of code. This is making it slightly harder for viruses to hide.

[pomop]

There isn't *one* virus that is undetectable by anti-virus programs. There are billions of different viruses and some of them disguise themselves so they won't be detected by anti-virus programs. I would be very surprised if there was a anti-virus program that detected every single virus ever made.
There are many good and free AV programs that you could try but I recommend you to delete your current one before installing the other. Two anti-virus programs on the same computer might cause problems.

Good free anti-virus programs:
Avast
Avg
Kaspersky

*All of these programs are trial versions which means you can use them for free for about 30 days. If you want to continue getting updates after the 30 days then you'll have to pay*

AVG is free... permanently. Well, you can pay, but the free version is able to do virus scans and get rid of them. Paying just gets you more.

http://free.avg.com/us-en/homepage