don't think pup.exe is a virus (not unless you include MS products in that category). To quote from MS
You can run Commerce Server Site Packager from the command line interface by using the run-time file, Pup.exe. Site Packager includes a set of command line switches that you use to perform tasks on sites and resources, including packaging, unpacking, and deleting a site or resource. In addition, you can establish unique resource references for custom installation requirements by using Microsoft Visual Basic scripts.
from here;

http://msdn.microsoft.com/library/de...c_pup_gcss.asp

what does the AV scan say about another virus... and which one are you using?

Z