Receiving E-Mails from External.....

I have recently join an environment that is not documented well.  First problem, my account has been created, in local domain and email setup in MS Exchange 2003 running on Windows SBS.  The account is able to send emails outside of the organzation without any problems.  However, when sending emails from an external account to this account I receive Recipient unknow 550.5.1.1 User Unknown error message.  Old users work fine but I have created a couple of new users with the same problem.  There are no more remaining IS individuals from the original group :-( so any assistance would be great.  I can answer any questions about the setup.  So far everything on the surface looks correct.
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Does the external mail name, match that of the Organization and the MX records, and DNS ?
If not, you may need to manually enter the secondary email address into the AD manually for new users.

I hope this helps !
romeoiceAuthor Commented:
Maybe I mis-spoke.  So the example is:

company email address is:
when mailing from I receive the user unknown message. MX record is setup with

Error message is below:
----- Transcript of session follows ----- ... while talking to
>>> RCPT To:<>
<<< 550 <>, Recipient unknown 550 5.1.1 <>... User unknown
What name is showing up for the Domain in the Virtual SMTP ?

DO all users only have 1 email address ?


to check to seeif you other Domain names set up, which should automatically allow receiving to alternate Domain names.

Did you check the AD settings if a working and nw account ?

I hope this helps !

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