false positive?

I recently updated from Avast 4 to 5. Subsequently a scheduled scan found Win32:Zwangi-f[PUP] in two System Volume Information files A0095496.dll & A0099031.dll. I then updated my definitions and restored the files. I scanned them one by one and they came back as no virus found. However, the next scheduled scan picked them both up and put them in the virus chest where they remain. They are both from old snapshots.
as infected. I need to know if they are false positives and/or should I wipe out the system restore files and restart or can I just keep going?

Sept2749 ???

Win32:Zwangi-f[PUP]
http://searchsecurity.techtarget.com/sDefinition/0,,sid14_gci1066761,00.html - A PUP (potentially unwanted program) is a program that may be unwanted, despite the possibility that users consented to download it. PUPs include spyware, adware, and dialers, and are often downloaded in conjunction with a program that the user wants.

BrowserModifier:Win32/Zwangi
http://www.microsoft.com/security/portal/Threat/Encyclopedia/Entry.aspx?Name=BrowserModifier%3AWin32%2FZwangi

you may check your computer for malware with

Malwarebytes Anti-Malware 1.46 http://filehippo.com/download_malwarebytes_anti_malware/
always update so you have latest database before you scan
click the remove selected button to quarantine anything found
you may post the scan log here

Thank you for the info. I use Anti-Malwarebytes and it finds nothing. I restored the 2 files and scanned them again and again they come up NO VIRUS. However, the next scheduled scan will probably pick them up as it did yesterday.I personally think they are false positives as I just updated from Avast 4 to 5 and these files were present and never tagged with Avast 4. I also searched for files this virus produces per the link you sent me from Microsoft and they are not present. What to do?