BleepingComputer.com: Avast Backfire?

I'd been using avast for a while, and it seemed pretty good, so I recommended it to a friend.

She tried it, downloaded it and installed it. After doing so, the ads that were bugging her were still there, her desktop wallpaper had been replaced by a virus warning and she couldn't change it, and there were problems opening some programs. She couldn't access some of them via shortcut or Start Menu, and others wouldn't work at all.

It might not have been avast, and probably wasn't, but I'd just like to make sure about that

An anti-virus program is not enough to remove this infection. No single product is 100% foolproof and can detect and remove all threats at any given time. The security community is in a constant state of change as new infections appear. Each vendor has its own definition of what constitutes malware and scanning your computer using different criteria will yield different results. The fact that each program has its own definition files means that some malware may be picked up by one that could be missed by another. Thus, a multi-layered defense using several anti-spyware products (including an effective firewall) to supplement your anti-virus combined with common sense and safe surfing habits provides the most complete protection.

Have your friend print out and follow the instructions for using Malwarebytes Anti-Malware (scroll down).

• If she encounter any problems while downloading the updates, manually download them from here and just double-click on mbam-rules.exe to install.
  
• When removal is completed, a log report will open in Notepad.
  
• The log is automatically saved and can be viewed by clicking the Logs tab in MBAM.

Note: If MBAM encounters a file that is difficult to remove, she may be asked to reboot the computer so it can proceed with the disinfection process. Reagardless if prompted to restart the computer or not, please do so immediately. Failure to reboot normally (not into safe mode) will prevent MBAM from removing all the malware.

If that does not resolve the problem then tell her to start a new topic in the Am I infected? What do I do? forum. Tell her to also post the MBAM log.