Update: I ran into this problem yesterday, and it was a little severe, all commands from prompt would error out.
Installing MS XP Updates solved it somehow... I think it was corrected with SP2 installed. Maybe an OS bug that was fixed.
Are you running SP2?
Case:NZXT Trinity Silver PSU:Apevia Aspire 500W UV Green Motherboard:Asus A8N-SLI CPU:AMD Athlon 64 3500 CPU Cooler:Zalman CNPS7700-Cu Video:2x eVga nVidia GeForce 6800XT (256MB DDR) RAM:2Gig (4x512 Corsair TwinX dual channel) HDD:160Gig Seagate Barracuda SATA, 200Gig Maxtor SATA III CD/DVD:LG DVD ROM, NEC 16XDVD+-RW
(\__/) This is Bunny. Put him in your
(='.'=) signature and help him on his way
(")_(") to world domination