Dear All, Hope you are doing well. We are in migration process of Domain users with mailboxes from Exchange 2003 in windows 2003 domain (abc.com, windows 2003 forest functional level) to Exchange 2007 in windows 2008 domain (def.com, windows 2003 forest functional level). Both are different forest and different exchange organization with same organization name (First Organization). So I setup test environment based on the above scenario. Using ADMT 3.1 I can migrated users successfully from windows 2003 to windows 2008. I created SMTP namespace sharing between exchange 2003 and exchange 2007 forest to use common SMTP address <users>@mail.com because of phase by phase migration. I created mail.com as accepted domain and set as non-authoritative domain in exchange 2007 and same in exchange 2003. After user migrated I moved mailbox from exchange 2003 to exchange 2007 using Move-Mailbox command in exchange 2007. When I send mails to migrated users from outlook client the following message displayed in queue. Identity: COPHPREX02\Submission\71438 Subject: Test @ 11:42 Pm Internet Message ID: <AE1680B2166B9F48A012DC144D5EBEDC08E205@ MAIL.mail.com> From Address: user.one@mail.com Status: Retry Size (KB): 8 Message Source Name: SMTP: From Exchange 2003 Source IP: 180.40.1.90 SCL: 0 Date Received: 12/3/2009 11:44:12 PM Expiration Time: 12/5/2009 11:44:12 PM Last Error: A local loop was detected. Queue ID: COPHPREX02\Submission Recipients: IMCEAex-_O=MHRIL_OU=FIRST+20ADMINISTRATIVE+20GROUP_CN=RECIPIENTS_CN=Test+2Euser@mail.com Here all the clients using cached exchange mode option but when I sent mail from Exchange 2003 owa it will go to exchange 2007 migrated users. How can I solve this problem? I am totally confusedPlease provide me a solution to solve this problem.

On Fri, 4-Dec-09 08:36:07 GMT, Saravanan.T wrote: [ snip ]>Last Error: A local loop was detected. > Here all the clients using “cached exchange mode” option but when I sent mail from Exchange 2003 owa it will go to exchange 2007 migrated users. How can I solve this problem? I am totally confused…Please provide me a solution to solve this problem…. I'd guess that you either haven't updated the Offline Address Book, oryour Outlook client hasn't downloaded the updated Offline Addresslso possible that you've got the recipient in Outlook'saddress completion cache. If you do, delete it and pick the recipientfrom the GAL.---Rich MatheisenMCSE+I, Exchange MVP--- Rich Matheisen MCSE+I, Exchange MVP