You can try symantec's removal tool found
here
Remember to disable system restore as directed in the instructions.
From instructions:
"Windows prevents outside programs, including antivirus programs, from modifying System Restore. Therefore, antivirus programs or tools cannot remove threats in the System Restore folder. As a result, System Restore has the potential of restoring an infected file onto your computer, even after you have cleaned the infected files from all the other locations."