Open Directory Authentication

One of my sites is moving away from Macs towards PCs, however want to keep one room configured with their mac server. When DHCP was moved off the mac server onto the windows server, the macs now don't authenticate properly.

We've updated the settings in Directory Utility, and it lists the usernames at the login screen, however when a user enters their password it doesn't actually log in (the login window just wobbles then goes back to the password prompt).

We have no access to the new DHCP server, as its a remotely managed site so we can't make any changes there, however we need to try and get the clients connecting to the server in order to make them workable.

Any help would be appreciated (especially since i don't have a deep enough mac background, so i'm learning on the fly)

The open directory server address can be supplied to OS X with DHCP, if this was the case then it may need to be added manually to the Macs or have the option created in the windows DHCP settings.

If the Macs do have an open directory server already configured manually on them then it's something else.

Does the new DHCP server push out the same search domains and DNS servers ?