RDC stopped working suddenly after hdd issue

My office runs SBS 2003 and all client computers at the office have XPP with
SP2 installed. One computer had a hard drive issue (drive contained
errors--they were automatically "fixed" with a reboot.) After the computer
did its thing, I noticed several oddities: RDC stopped working for incoming
connections (I can still use it to connect to other computers just fine),
several control panels (such as add/remove software, device manager and the
advanced tab of network properties) stopped working.

I reinstalled XPP (dirty) and ran all the software patches on this machine.
The control panels now work, but I still can't connect to this computer
using RDC. I can connect to every other computer on the network from this
computer with no problem.

I've double checked this computer's remote tab, and remote connections are
allowed. The computer functions normally and it can connect to other
computers on the network using RDC. Even odder, I can't connect to this
computer from the SBS server. Software firewall is controlled by the SBS
machine under a group policy (as it is for everyone) so I know that's not an
issue. This computer doesn't have a third party software firewall.

For fun, I ran RDC on this computer, typed in its own IP address, just to
see what would happen. The screens darkened and the computer would no longer
function. I had to hold down the power key to force a shutdown.

I can't even ping this computer from other machines on my local network.

I am completely stumped. HELP!