According to some posts:

Don't export your pst as a pst, it loses data?
Don't import a pst, it loses data?
Is this function broken and unfixable?
Don't copy your pst to another machine, then connect with it because it will
create duplicates if the messages are still on the server? Something about
the messages being downloaded already isn't stored in the pst.

From long ago, you could run more than one machine against the same pst as
long as they both were connected at same time. Is that still true?

Is there a list of these do's and don'ts somewhere?

Norman