# SMTP Problem in Exchange - 550 must be authenticated



## mattyjonesuk (Sep 18, 2007)

Hi

Got into work this morning to find that noone can send emails and when sending mail to an external email address they recieve this message:

_There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<jomc.co.uk #5.5.0 smtp;550 must be authenticated>_

I have narrowed it down now to the settings in the SMTP connector and the error seems to be coming from 1and 1 when I relay mail through auth.smtp.1and1.co.uk

I have called them up and they claim there is no authentication settings but if that is correct then i am not sure why this error is coming up..

When i turn off the setting to forward though 1and1 then most emails send. I need to set up the relay so that certain clients can recieve emails though.. Please Help!!

Thanks
Matt


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## Machine_ (Jun 11, 2008)

OK I have 1and1 and they know better then to let people hang over this issue it's a simple E-mail configuration. I don't know what program you use but this is how to solve your problem using Microsoft OutLook.

Go to Tool>Options, Select the "Mail Setup" tab. Under the words "E-mail Accounts and to the right of the words "Set up e-mail accounts and directories" there is a button labled "E-mail accounts" press it. Make sure the "View or change existing E-mail accounts" radio button is selected and click next at the bottom. Select your pop.1and1.com account and click the button to the right labled "Change". You will be shown your e-mail settings for this account. At the lower right corner of the menu will be a button labeled "More settings" Click it. Go to the "Outgoing server" tab and put a check in the box labled "My outgoing server (SMTP) requires authentication" under that you will see 2 radio buttons, Select the button labled "Use same settings as my incoming mail server", Click "OK" then click "Next" at the next menu, then click "Finish" at the next menu and finally "Ok" at the last menu. Restart Outlook and you should be fine.

Have a Great Day,

Machine


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