550 no such user here - bounce error message when sending
Posted by Stephen Williams on 17 September 2014 05:10 PM

A '550 No such user here' is caused by authentication not being enabled for SMTP in Outlook.
To fix this -

1. Open Outlook

2. From the Tools/File menu select Account Settings. The Account Settings box appears.

3. Verify that the E-mail tab is selected. Your email account appears, usually labelled

4. Click on the account to highlight it, and click on the Change icon above it. The Internet E-mail Settings appear.

5. Under the Server Information section, in the box marked Outgoing mail server (SMTP) change the entry to (if it isn’t already set to this)

6. Click the button More Settings… in the lower right-hand corner. The Internet Email Settings box appears.

7. Click on the tab Outgoing Server.

8. Click the tick box “My outgoing server (SMTP) requires authentication”, and verify that the circle-box “Use same settings as my incoming mail server” is selected.

9. Click OK to close the Internet Email Settings box.

11. Click the Finish button to close the Internet E-mail Settings box. Click the Close button to close the Account Settings box. SMTP authentication has now been enabled.

Kind regards

Stephen Williams

Technical Support Engineer

Hosting UK
Tel: +44 (0)1745 586070
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