How to Enable DCOM in winXP?

Sir/Ma'am I have a problem in ASSET management - Windows Domain Scan. Most of the Workstation that i have scan is failed. almost all of the workstation in the inventory list is failed and it say " Failed Either access denied for the user or the remote DCOM option might be disabled in the workstation. HOW CAN I ENABLE DCOM? Actually when i format all the workstation here, i didn't enable or disable DCOM, how come that some of the Workstations I scan is success when i scanned it, while most of the other workstations failed in scanning. im using windows 2000 server and i used windowsXP Pro. in the workstation. I also used the administrator login and password. Can you help me on problem.?

thank you,
Erwin