Change Roles via Registry Server 2003

Modify the ProductType entry in the registry. To do this, follow these steps:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\ProductOptions ProductType.

Type ServerNT for Member Server

Type LanmanNT for Domain Controller

Note If this value is not set correctly or is misspelled, you may receive the following error message:
System Process – License Violation: The system has detected tampering with your registered product type. This is a violation of your software license. Tampering with product type is not permitted.