I have taken a SBS2003 server, and used local move request to import all mailboxes into exchange 2010, then, used export-mailbox command to put them into a *.pst file.
Now, set up a new exchange server, and used import-mailbox to put them all back in.
Now, using outlook, any e-mails John Smith sends me, come up John smith, no problem, but any emails John Smith sent me before the changeover, appear at the bottom of outlook as //FIRST ADMINISTRATIVE GROUP/JOHN SMITH and clicking "reply" says "could not find this recipient" I have tried removing contact, editing contact, adding contact, etc. I have also checked the GAL and it only shows the current contact on the current server.
Further. If i go to send a NEW email to say Reception@server.com it gets there no problem, and reception can reply back to me. HOWEVER, if reception emails me (a new email, not one from before the changeover), then if i click reply, it bounces back to me, and says "Reception@server.com - there is a problem with the users mailbox". If i click reply, clear the recipient field, and manually type back in firstname.lastname@example.org it resolves, and still bounces back saying error. BUT if i go to create a NEW email, and type in email@example.com, it resolves to the same address, same contact, but this time it sends no problem.
Have tried really hard to search through internal contacts, GAL, and client contacts to find any double ups or wrong settings but it seems so strange that the address letter for letter appears perfectly correct, and the exchange server mails me back with the exact address saying there is a problem with the mailbox. Outside clients can email them back and forth no problem, and i can send new emails, but i cannot reply to them. This is happening with most of our internal contacts, but even though i have erased them all at the outlook client, they still seem to resolve to the correct address, but the wrong location.