How is your PC running?
If a virus infects a computer with this operating system the virus can be backed up
in the System Restore folder.
Clearing the restore points is necessary after a virus removal. To reset your restore points, please note that you will need to log into your computer with an account which has full administrator access. You will know if the account has administrator access because you will be able to see the System Restore tab. If the tab is missing, you are logged in under a limited account.
1. Turn off System Restore.
On the Desktop, right-click My Computer.
Click Properties.
Click the System Restore tab.
Check Turn off System Restore.
Click Apply, and then click OK.
2. Reboot.
3. Turn ON System Restore.
On the Desktop, right-click My Computer.
Click Properties.
Click the System Restore tab.
UN-Check *Turn off System Restore*.
Click Apply, and then click OK.
To help keep your PC clean follow the recommendations in Tony Klein's article
So how did I get infected in the first place?