Keyboard/remote connect no longer respond-multiple workstations

After the latest round of MS updates (as of 12/22/08) including IE patch and
java update, I have four systems that exhibit no keyboard and I cannot log in
using remote connect. Three systems have the same hardware. Booting into bios
- keyboard responds, exit to windows - may or may not have a working
keyboard. Running XP Pro (3 on one domain, 4th on another). One usb keyboard,
the others PS2 with KVM switch, although I have tried plugging in usb with no
results. Before I roll back pre updates, I am looking for help. Multiple
other workstations (at least 5 more with the same hardware) exhibit no
problems.