EXCHANGE SERVER is able to receive email and send email to internal user,but is not able to send mail to external users (like user@yahoo.com), the error message is :
externalusername@yahoo.com on Sat, 16 Feb 2002 13:22:44 -0800
The recipient name is not recognized
The MTS-ID of the original message is: c=US;a=
;p=server domain name;l=EMAIL0202162122FCG5BB2J
MSEXCH:IMS:domain name:domain name:EMAIL 0 (000C05A6) Unknown Recipient
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any idea is appreciated!