OS X Lion Server hangs on install ("authenticating")
I'm trying to update my headless/keyboardless/mouseless Mac Mini Server (mid-2010) running OS X 10.6.8 Snow Leopard Server. I've been able to download Server.app from the App Store without problem, but when I run it, it asks for my admin password and hangs at the "Configuring Services" dialog with an "Authenticating" message in the bottom left corner. It appears to be hanging at this authentication bit.
WHAT I DID
Installed Lion.
Downloaded Lion Server from App Store.
Launched Server.app.
WHAT I EXPECTED
Lion Server to install.
WHAT HAPPENED
Hangs at "Configuring Services" dialog with an "Authenticating" message in bottom left corner.
Eventually times out with a "The request timed out" error message.
Help?
Mac mini, Mac OS X (10.7), Lion Server