Hello, Hoping someone could help with this error im getting. When i do a mailbox move from 2010 to 2013 using the 2013 Gui. I get an error saying ...... Cannot open mailbox /o=First Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Configuration/cn=Servers/cn=EXCHANGE/cn=Microsoft System Attendant. Environment details are: DC 2008r2 Exchange 2010 on 2008 r2 Exchange 2013 on 2008 r2 Has any come across this before? Thanks

hi, this blog has the answer for your error. http://social.technet.microsoft.com/wiki/contents/articles/15842.mailbox-migration-fails-with-error-cannot-open-system-attendant-mailbox-in-exchange-server-2013.aspx get-mailbox -arbitration Regards Viman

Hi Viman Thank you for the reply, I checked out the article but still no luck, Both my databases are mounted. Any other ideas? Thanks for your help.

Hi, Apologies if this seems really obvious but did you upgrade to CU1 and is Exchange 2010 at SP3? What happens if you try to move the mailbox via the Exchange 2010 GUI? H

hi, this blog has the answer for your error. http://social.technet.microsoft.com/wiki/contents/articles/15842.mailbox-migration-fails-with-error-cannot-open-system-attendant-mailbox-in-exchange-server-2013.aspx get-mailbox -arbitration Regards Viman

Did you delete the default mailbox database which got created automatically during the installation?

Did you delete the default mailbox database which got created automatically during the installation?

We're running into the same issue, moving from Exchange 2007 to 2013. All of the most recent patches and rollups are installed on all servers. All databases are showing as mounted, and all necessary mailboxes return in the get-mailbox -arbitration request. DC 2008r2/2012 Exchange 2007 (version 8.3, build 83.6) on 2008r2 (1 CA, 1 HT, 3 MB servers) Exchange 2013 (version 15.0, build 516.32) on 2012 (1 CAS, 2 MB servers) DAG with 2 servers, 2 databases Appreciate any feedback! Royal