MonitorWare Knowledge Base

I am currently running my network in mixed mode with a very old DC that I want to get rid of. It is the PDC for pre-win2000 pc's right now. I would have thought that all I had to do was change the roles in the Operations master to affect the change I wanted. However, after doing this and shutting down the old DC as a test, I found that no one could log into the network, let alone pre-2000 machines...What did I do wrong or forget?