Solved

550 5.1.1 User unknown

Posted on 2012-04-03
14
518 Views
Last Modified: 2012-08-15
Hello, I'm trying to send a message from outside to a known e-mail address  but am coming across a 550 5.1.1 ... User unknown error message.
Emails to another mailboxes of the same domain receiving without any issues. AD user of this mailbox is not locked and disabled.Mailbox is not full. Receiving emails from internal users working. Please assist
0
Comment
Question by:twolines
  • 6
  • 6
14 Comments
 
LVL 76

Expert Comment

by:Alan Hardisty
ID: 37800935
Well - the obvious answer is that the mailbox doesn't exist - but it may be that the mailbox server is clustered and one of the clusters is missing the mailbox and needs updating.

Are you sure the address is still valid?
0
 

Author Comment

by:twolines
ID: 37800941
Yes, the address is valid, I wrote above that this mailbox can receive emails from internal users but from outside - no. Other mailboxes of this domain can receive emails from outside, but this mailbox - no.
0
 
LVL 6

Expert Comment

by:awaggoner
ID: 37800945
Are you using a spam/content filter?  Some of the cloud based services allow you to configure it so only valid email addresses can receive mail.  The problem is that you must maintain your addresses with the service.  Is this a new mailbox or an existing one.

Are you able to send email from the address to your outside account?  After receiving a test email from the internal account to the external one, do a reply back to the sender.

Can you find the messages in Exchanges Message Tracker?
0
 

Author Comment

by:twolines
ID: 37800967
There is no spam/content filter.  This is not new mailbox, this is existing one. In the beginning of March this mailbox was moved from one mailbox database to another. I can receive emails from this mailbox, but when I click reply and send back, still receiving 550 5.1.1 User unknown
0
 
LVL 76

Expert Comment

by:Alan Hardisty
ID: 37800985
Do you have access to both servers?
0
 

Author Comment

by:twolines
ID: 37801028
Yep. Provider has Exchange 2007 (mailbox in question) and Exch2010  and answer User unknown comes from HUB of 2010
0
Does Powershell have you tied up in knots?

Managing Active Directory does not always have to be complicated.  If you are spending more time trying instead of doing, then it's time to look at something else. For nearly 20 years, AD admins around the world have used one tool for day-to-day AD management: Hyena. Discover why

 
LVL 76

Expert Comment

by:Alan Hardisty
ID: 37801034
Has the Exch 2007 GAL been updated since the mailbox move?
0
 

Author Comment

by:twolines
ID: 37801039
Yes
0
 
LVL 76

Expert Comment

by:Alan Hardisty
ID: 37801066
And is the default Email address showing on the 2007 server correct?
0
 

Author Comment

by:twolines
ID: 37801070
yes, email address is correct
0
 
LVL 76

Expert Comment

by:Alan Hardisty
ID: 37801171
Can the mailbox be moved back to where it came from?
0
 

Author Comment

by:twolines
ID: 37801312
Nope
0
 
LVL 76

Accepted Solution

by:
Alan Hardisty earned 500 total points
ID: 37802447
Can you please post the headers of an email from the problem user and obscure the email address / IP Addresses / Domain Names etc.

Thanks

Alan
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Are you irritated by repeating emails issue in Microsoft Outlook 2016 after recent update ?  Lets’ see how to resolve and prevent duplicate emails in the Outlook 2016 using some simple techniques.
Read this checklist to learn more about the 15 things you should never include in an email signature.
To show how to generate a certificate request in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.:  First we need to log into the Exchange Admin Center. Navigate to the Servers >> Certificates…
This video demonstrates how to sync Microsoft Exchange Public Folders with smartphones using CodeTwo Exchange Sync and Exchange ActiveSync. To learn more about CodeTwo Exchange Sync and download the free trial, go to: http://www.codetwo.com/excha…

863 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

24 Experts available now in Live!

Get 1:1 Help Now