What version of WHS are you running?
That file is a component of a known trojan,
CRYPTER.A. It sounds like you've had a virus infection which was incompletely cleaned up. If you've recently installed WHS, you might want to consider a fresh installation, abandoning all data currently on the server. That would be your safest option; the WHS DVD (or the downloaded .iso, assuming you're running a beta version and downloaded it from Connect) isn't going to be infected.
If this is actually a WHS client PC with the problem, then I would recommend you pop in the Rescue CD from whatever AV product you're using and see if it can finish the cleaning up of the infection. And I would then remove the PC from the WHS console and run a backup cleanup, to make certain that you don't have a backup of the infected PC.
