I have an installation with Office 365 showing Outlook version 2013.
I believe the Outlook .pst file is one that has moved forward as Outlook versions has evolved.
I don't know the implications of this or if it's really even possible.
But, the Inbox has been allowed to get huge and the program now won't delete message. It says something about the file being too large and being pre-2003 I think was the year given.
So, I'm working on creating a new file and moving some of the messages.
In the mean time, if I click on People, we don't see a very long list of addresses. But, if we start a New message, the To: line search will bring up many. I'm confused. Where are those addresses and how can I be sure to move them into the new .pst file?