Message received when trying to recall an e-mail: You do not have permission to send to this recipient.

I have two users on our network whom, when trying to recall e-mails they have previously sent out succesfully, they receive the following message:

Your message did not reach some or all of the intended recipients.

      Subject:Recall: test
      Sent:6/26/2013 10:08 AM

The following recipient(s) cannot be reached:

      Gesner, Tim on 6/26/2013 10:08 AM
            You do not have permission to send to this recipient.  For assistance, contact your system administrator.
            MSEXCH:MSExchangeIS:/DC=local/DC=cofrexch2003:COFREXCHANGE2

As far as I can determine - the recall should work (we have several other people on the network who can recall messages, just not these tow users.

Both the original sender and the person being sent to, ar on the same network/domain.

My Ideas: (not attempted yet)

1.  delete and create a new Outlook profile on the computer.  

2.  Delete and re-create a new .nk2 

Thanks