It's doubtful if anyone has experience with
PWS:Win32/Sinowal.gen!U since it was added to the Malware Protection Center Database on 2/25/2010, but you can inquire at the Safety Scanner support forums:
http://boards.msn.com/safetyboards/forum.aspx?ForumID=13They will want to know the location of the detected infection as reported in the Safety Scanner Results Window, and at a minimum, your OS (32 or 64 bits), browser/version, and installed AntiVirus/Anti Spyware/Firewall.
How to determine whether a computer is running a 32-bit version or 64-bit version of the Windows operating system
Regards, Dave