I spent a lot of time fighting this and just thought I'd post my $0.02.
I reinstalled the drivers as mentioned above. That was a bit of a painful process of uninstalling, rebooting, and re-installing.
I started trying to use Eterlogix VSPE as mentioned in the PE micro serial re-director program. I never did get the serial redirect to work with VSPE.
I ended up trying com0com, and that seemed to do the trick.