Oh, my first contact with Exchange was discovering that the recently updated server couldn't read any of the backups on the proprietary format of the pre-update version of it. It seemed to be a common enough occurrence, because the email people just shrugged and started hacking the backup. I don't think that group was ever capable of restoring any Exchange backup, normally because of Exchange's problems.

But that was a long time ago. From what I hear, things are different now.