fai il fix a queste voci di hijackthis:

C:\WINDOWS\system32\Instmtv.exe

O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)

O4 - HKLM\..\Run: [snp2uvc] rundll32.exe C:\WINDOWS\system32\csnp2uvc.dll,ResetCIDS

O4 - HKLM\..\Run: [Microsoft Driver Setup] C:\WINDOWS\system32\Instmtv.exe

O4 - HKLM\..\Policies\Explorer\Run: [Microsoft Driver Setup] C:\WINDOWS\system32\Instmtv.exe