I am unable to send email to a certain us.mil address. Here is the message: Delivery has failed to these recipients or distribution lists: user@us.af.milAn error occurred while trying to deliver this message to this recipient e-mail address. Microsoft Exchange will not try to redeliver this message for you. Please try resending this message, or provide the following diagnostic text to your system administrator. The following organization rejected your message: 52VEJXEG002.amc.af.mil. _____ Sent by Microsoft Exchange Server 2007 Diagnostic information for administrators: Generating server: mailserver.domain.com user@us.af.mil52VEJXEG002.amc.af.mil #550 Mailbox unavailable or access denied - <user@us.af.mil> ## Original message headers: Received: from MailServer.domain.com ([fe80::1]) by MailServer.domain.com ([fe80::1%1])with mapi; Wed, 19 Aug 2009 10:22:53 -0400From:User <user@domain.com>To: "user@us.af.mil" <user@af,us.mil>Date: Wed, 19 Aug 2009 10:27:17 -0400Subject: Sol. F1T0EJ919A001 Training for 8570 RequirementsThread-Topic: Sol. F1T0EJ919A001 Training for 8570 RequirementsThread-Index: Acog2ScI9wP9wEcHS/mXSwMc+MmC+Q==Message-ID: <5CF82F642F3A364E9016B8DB413B6D24BADF956AD6@MSPX12.mspx.com>Accept-Language: en-USContent-Language: en-USX-MS-Has-Attach:X-MS-TNEF-Correlator:acceptlanguage: en-USContent-Type: multipart/alternative; boundary="_000_5CF82F642F3A364E9016B8DB413B6D24BADF956AD6MSPX12mspxcom_"MIME-Version: 1.0Any help will be greatly appreciated.

This message doesnt contain any detail as to why you cannot send other than they are actively rejecting the message. this means the mailbox is either nonexistent or they dont like your connection for reasons undisclosed. being a military domain, this does not surprise me. I would look to make sure you have valid SPF records, and PTR records and make sure you arent on any RBLs. Otherwise you need to contact the recipient and troubleshoot from their end. Mike Crowley A+, Network+, Security+, MCT, MCSE, MCTS, MCITP: Enterprise Administrator / Messaging Administrator Read my 2 on the Psychology of a TechNet Forum Thread!

Thanks Mike. It turns out that this email address is incorrect. Sorry to waste your time. Thanks.