Login error -“Path to long”

Has anyone seen this one before? After restarting this one computer with NT 4.0 SP6a installed, I get a log in error. The error says, “Can not access that folder. Path is to long.”
The only changes made to this system was adding a couple of com ports after the first two quit. The strange thing is that these first two com ports were working fine in HyperTerminal not that long ago. Could this be the product of a virus?
I really need access to this computer, and not sure what to do. Help!, Thanks!