I was setting up a Lion Mac mini Server for a client and after changing the local administrator’s password, I was unable to access any of the services via either Server Admin or the Server application. Fortunately there’s an answer at hand, courtesy of the internets, particularly this post on the MacRumors Forums. Somehow the the Server Manager Daemon has got itself unloaded, which isn’t a good situation to be in, however fortunately a fix is very easy. Enter the Terminal and type in:
sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.servermgrd.plist
Boom! Fixed.