Email bounce back 550 5.1.1 recipient rejected

Stan asked:

A client recently switched to Exchange Server / Outlook for their email. Since then emails from my company to any email address at their company bounce back from the System Administrator with this error:

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

   Subject:  Email Solution
   Sent: 12/12/2012 11:08 AM

   The following recipient(s) cannot be reached:

   '[email protected]' on 12/12/2012 11:08 AM
    550 5.1.1 <[email protected]> recipient rejected

Looking in the Message Options of the bounce back email shows no data in the Internet Header field.

My client’s IT guy says we’re not being blocked, but I cant think of any other reason the bounce would occur.

Any suggestions on what questions to ask or how to fix this would be helpful.

I’m using a desktop version of Outlook 2007 and connecting through my ISP.


My answer:

550 5.1.1 means that the recipient email server believes that the email address does not exist at the destination domain, and therefore has no way to deliver it.

Unless you simply made a typo in the email address, this is not something that you can fix, and must be addressed at the other end.

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