Hi, I have a strange one. A user sent an email to another user, both being on the same Exchange server (i.e. configured users on the Exchange Server). The email bounced to the sender with this error message to the sender: ------------------------------------------------------------------------- The e-mail account does not exist at the organization this message was sent to. Check the e-mail address, or contact the recipient directly to find out the correct address. <xyz.ourexchangeserver.com #5.1.1> ------------------------------------------------------------------------- But the recipient email account positively exists, and has been there for some months. Earlier and subsequent emails succeeded without a problem. And others can send to this same user. I checked the the relevant log file under \Program Files\Exchsrvr\XYZ.log directory, and there is no trace at all of this email having been sent by the sender (I looked pretty carefully using searches etc.). Yet she received an error message from the server. Any suggestions where I should look next? Mike