Just got infected...AV Security virus

I have windows Vista and Avast 5.0.545 and I have this virus or whatever…AV Security Suite,

How do I get it off?..and how did it get on??
I ran an Avast scan and it wasn’t picked up, said all was fine. It can’t be deleted

it’s in Appdata/local /temp as an application

Is avast making any detections and if so are they coming back ?

If not how is it that you know, fake security alerts, etc. ?

If it keeps coming back, there is likely to be an undetected or hidden element to the infection that restores or downloads the file again. What is your firewall ?

If you haven’t already got this software (freeware), download, install, update and run it and report the findings (it should product a log file).

Don’t worry about reported tracking cookies they are a minor issue and not one of security, allow SAS to deal with them though. - See http://en.wikipedia.org/wiki/HTTP_cookie.
Also available a portable version of SAS, http://www.superantispyware.com/portablescanner.html, no installation required.

Yes, I’m getting fake security alerts constantly and when I decline them porno pages open up.

Avast did not detect anything, I ran a scan and scanned the file, both came back clean. I have a firewall through Avast

I installed MalwareBytes Anti-Malware but it will not let me run the program, it says it’s an infected program and I should install their ( AV Securities) antivirus software.

I never had a problem with the older free version of Avast I was using till just a few days ago.

How to remove AV Security Suite (Uninstall Guide)
http://www.bleepingcomputer.com/virus-removal/remove-av-security-suite

important that you follow the guide step by step for it to work

@ lkcoss
Try running MBAM in safe mode.

http://www.bleepingcomputer.com/virus-removal/remove-av-security-suite