wcwdu16814728.exe and Popup Windows

Can anyone help me with this virus?  It's generating a Windows Security Centre Alert like this one.  I'm not sure how to get rid of it does anyone have any suggestions?  I've read a few forums and run some scans but nothing is detecting it.  I ran a full sweep with Norton, but it's still active in my process.  I can see the .exe on my c:\ drive and I can see it running under systems process and today I cannot access Norton on my pc, so I am unable to check for updates as recommended in discussion forum here.