Thought I’d write a quick blog article on an issue I had with my Mac at work. We have Leopard Server running on a Mac Pro, and use Kerberos for authentication of machines on the network when connecting to services such as iCal Server.

A few months ago, my work machine (a MacBook Pro) started complaining when iCal was running and kept asking me for my Kerberos password. I’d enter it, and it would respond telling me that Kerberos login had failed. No one else in the office had this issue.

Eventually I compared my ~/Library/Preferences/edu.mit.Kerberos.KerberosLogin.plist with that of a colleague and found they were different. The key difference was that a number of keys had changed type from Boolean to Number. That is, I had:

And they had:

(YAMATO is the name of our server machine).

Changing the types to Boolean fixed the issue.

The question is, how did my machine get into this state? I believe the answer is MobileMe. I had my machine at home and my machine at work syncing through MobileMe, and I included in this sync the syncing of Preferences. I believe the machine at home, that had never connected to Leopard Server, had the “bad” plist, and at some point the plist on the work machine was replaced (or merged) with the home machine.

I’ve turned off Preferences syncing, and continue to use other sync features of MobileMe without issue (for the record, I love MobileMe – it is especially good when you have multiple machines to sync, in my case a number of Macs and an iPhone). This may be a bug with MobileMe, but given how few people use Leopard Server, and of them an even smaller percentage use MobileMe, it isn’t surprising that no one has noticed.

Hopefully if someone is having this issue they will find the solution here.