Hi, We had a SBS 2003 server with exchange 2003 and have recently installed a new server and have installed SBS 2008 with Exchange 2007. Evrything works fine except one issue with exchange. The old server was setup by someone else and had all sorts of rules and GPOs which i wasn't aware of so we went for a clean build. For exchange we exported the emails to PST files and then uploaded to the users mailbox in exchange 2007. There able to send new emails (internal and external) without any problems but when the reply to a email sent to them prior to the upgrade the get a bouceback with the following error. This problem is also only when replying to old internla emails. Delivery has failed to these recipients or distribution lists: 'Users Name' The recipient's e-mail address was not found in the recipient's e-mail system. Microsoft Exchange will not try to redeliver this message for you. Please check the e-mail address and try resending this message, or provide the following diagnostic text to your system administrator. _____ Sent by Microsoft Exchange Server 2007 Diagnostic information for administrators: Generating server: EMEA-UK-DC-1.domainname.local IMCEAEX-_O=STICKY_OU=FIRST+20ADMINISTRATIVE+20GROUP_CN=RECIPIENTS_CN=Recepient's email address> #550 5.1.1 RESOLVER.ADR.ExRecipNotFound; not found ## Original message headers: Received: from EMEA-UK-DC-1.Domainname.local ([fe80::14bb:56fd:52e9:c604]) by EMEA-UK-DC-1.stickycontent.local ([fe80::14bb:56fd:52e9:c604%15]) with mapi; Mon, 18 Apr 2011 16:11:24 +0100 Content-Type: application/ms-tnef; name="winmail.dat" Content-Transfer-Encoding: binary From: Senders name <Sender's email address> To: 'recepient's name'' <IMCEAEX-_O=STICKY_OU=FIRST+20ADMINISTRATIVE+20GROUP_CN=RECIPIENTS_CN=Recepient's email address> Date: Mon, 18 Apr 2011 16:11:24 +0100 Subject: Email subject Thread-Topic: email subject Thread-Index: Acv2DdTje/2yGihsTdiHhzzHtmAeWwCHPl9AAJ4m6MAAzP/FsAAAyfAgAAAR20A= Message-ID: <652867A266795048B7E447B756EC23D57FABCD94@EMEA-UK-DC-1.domainname.local> Accept-Language: en-US, en-GB Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: <652867A266795048B7E447B756EC23D57FABCD94@EMEA-UK-DC-1.domainname.local> MIME-Version: 1.0 When replying to the old email i have checked the email addresses and their default email address is not showing. I'm guessing it is looking for the old GAL but can't find it as it is now exchange 2007. What can i do to get this working? Thanks

There could be many factors causing this issue, please see the thread and take those action one by one & see if they help you. http://social.technet.microsoft.com/Forums/sk-SK/exchangesvradmin/thread/c1fab3bd-589d-4c7c-8807-2eda93d11c27 Keep us updated please.Regards, Pushkal MishrA

Any update please??Regards, Pushkal MishrA

Hi K7Hari, This may because after a migration, when you try to reply old emails, exchange will try to send this mail using legacyexchangedn of old user. To prevent this problem you can add the old legacyexchangedns to users as x500 address. You can get more information from these: Cannot Reply To Old Emails Or Modify Old Calendar Items After PST Mail Migration http://blogs.technet.com/b/sbs/archive/2009/05/21/cannot-reply-to-old-emails-or-modify-old-calendar-items-after-pst-mail-migration.aspx Cross Forest Migration using ADMT 3.1, Mailboxes moved but cannot reply to emails from Exchange 2010 http://social.technet.microsoft.com/Forums/en-US/exchange2010/thread/f99244d7-facf-4ad9-a83e-f6d3baa1ba8b/ Thanks, Evan Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.