can't send external message from microsoft exchange
Posted on 2013-10-24
I recently got a task at my job, for creating a new mailbox account on the exchange server. I am able to send and receive mails inside my organization and able to receive mails from outside my organization (ex: google, yahoo, etc). I can't send mail outside. I get this error:
Your message wasn't delivered because the recipient's e-mail provider rejected it.
The following organization rejected your message: mx.mydomain.com
mx.mydomain.com #550 5.7.0 no DKIM signature data ##
Before this problem, i couldn't do anything with the account (no sending, nor receiving from inside and outside). To get it work, i made an e-mail adress policy an applied it with priority 1.
More details about the environment:
-MS exchange 2010
-many domains in the accepted domanis list (including the one which has the account with problem)
-there is a messaging gateway for spam filtering from Symantec, but there are no problems there.
-parallels plesk panel; no problem there as well
The ISP isn't blocking the smtp port. All the other domains listed in accepted domain list, among with their mailboxes, are working fine.
The issue must be somewhere in the Microsoft Exchange, but i don't have a clue where.
Any help would be highly apreciated.