What's best free antivirus for windows vista?

I've installed Malwarebytes Anti Malware and it works pretty well. And I've also installed free trial version of Avast. However it doesn't seem to be compatible with my Vista. Since I installed it, error message regarding 'unauthorized to change window' keeps popping up, and eventually I had to uninstall Avast. Now I'm still looking for best anti virus. Avast is NOT compatible with vista

Try this: I have the free versions of Malwarebytes' Anti-Malware (MBAM) and Avira Antivirus installed. They won’t conflict, so long as you don’t attempt to scan with both simultaneously. Avira does have occasional pop-ups trying to persuade you to upgrade to the paid-for version. If this puts you off, I recommend downloading Avast instead. Here’s a link to the free version of Malwarebytes’ Anti-Malware: http://www.filehippo.com/download_malwarebytes_anti_malware/ Here’s a link to the free version of Avira Antivirus: http://www.filehippo.com/download_antivir/ Here's a link to the free version of Avast: http://www.filehippo.com/download_avast_antivirus/ Hope this helps.

I would recommend Immunet Free antivirus software- http://www.immunet.com/free/index.html

The best antivirus is avast 7 it needs much time to scan but can remove any virus from ur pc it has other various functions best of luck

I think best is quickheal or netprotector.....

it's avira only

TPB