There are many changes in Exchange 2013. Some of them are major changes but most are minor. However, some changes aren't mentioned anywhere. A couple of days ago, I noticed a few changes that really doesn't make any sense at all. I was attempting to transition an Exchange 2003 environment to 2013. Granted, this transition isn't supported and indeed not possible in a normal sense. Still, when transitioning from one Active Directory to another, this doesn't matter as we'll be using PST-files to copy mail content.
Using the trusted, old ExMerge tool, I began extracting all mailboxes below 2GB. After copying the files to the Exchange 2013 server, I then ran the command to import the PST-files to the appropriate mailboxes. Lucky for me, I decided to start with just one mailbox and see how it went. The new mailbox was of course riddled with gibberish causing much distress to the user in question. After some research, it appears that Exchange 2013 as opposed to its predecessors cannot handle PST-files in Ansi format. A rather strange feature to remove in my opinion.
Well, it doesn't end there. Once I was able to import the PST-files after converting them to Unicode, it would appear that the localized names of the folders have been changed. For instance, instead of just using the old name "Sent", this has now been changed to "Sent objects". What was wrong with the old folder names that have been used since... Well, since forever.
Still, it was worth it in the end as Exchange 2013 is just so much better than 2003.