Can not connect to its own share mapping or publish itself

Setup: - The following setup has been working for a few
months. It just started to fail yesterday.

I have an XP Pro system in a workgroup setting that has a
folder shared up for use. We acesse the folder via a
drive mapping from other XP machines on the network, as
well as this machine itself.

Problem:
The system does not broadcast itself within the workgroup
anymore and the drive mapping that is on the machine
itself is disconnected. The system does have internet
connectivity so IP is working. I have run virus scanners
and Adaware programs agianst the system. We did not find
any viruses and did find a lot of Adware/Spyware which
Adaware took care of.

Any ideas???

Thanks,
Steve