I'm responsible for two separate but related organizations. Prior to my arrival here, a single Exchange 2010 server was in place with the users of one domain assigned User Mailboxes, and users of the other domain assigned Linked Mailboxes. 

I'm trying to break this apart & have those linked mailboxes be user mailboxes in their source domains attached to the already existing users. I'm attempting to use the Prepare-MoveRequest.ps1 script to facilitate this, but get the following error:

The operation couldn't be performed because object '{DC/OU/CN}' couldn't be found on '{domain controller FQDN}'.

Cannot create mail enabled user because an existing object with type  already has the same proxy address/MasterAccountSid.

I've set the -UseLocalObject switch in the command, and I'm certain the user exists in the location returned by the error.

You wouldn't do that with a move request because you're not moving the mailbox like you would be doing to a different Exchange server, you're just associating it with a different user account.

The supported method of doing this is to disable the mailbox, then enable the mailbox with the correct user account in the local forest.

Here's a link to an unsupported method I found for you, but it's for Exchange 2007.  I don't know why it wouldn't work the same way, but use it at your own risk.

http://www.msexchange.org/kbase/ExchangeServerTips/ExchangeServer2007/ManagementAdministration/ConvertingaLinkedMailboxtoaUserMailbox.html

Hi Carl,

Thank you for your question.

The Prepare-Moverequest must match three attributes: Proxyaddresses, mail and mailnickname. So we create a new notepad file and name it admtexclusion.vbs, then enter the following line:

Set objMig = CreateObject("ADMT.Migration")objMig.SystemPropertiesToExclude = "homeMDB, homeMTA, showInAddressBook, msExchHomeServerName, msExchRecipientTypeDetails, msexchrecipientdisplaytype msExchMailboxSecurityDescriptor, msExchMDBRulesQuota, msExchPoliciesIncluded, msExchUserAccountControl, msExchVersion, mdbusedefaults"

Then run the file on ADMT server.

Finally, we could run the script to check if the issue persist.

If there are any questions regarding this issue, please be free to let me know. 

Best Regard,

Jim

Thank you very much for the replies. Maybe I wasn't clear enough about my setup. There are two seperate organizations with their own AD domains & Exchange organizations. There's a forest trust and network connectivity between them. Users in domain2 have linked accounts in domain1's Exchange org. My understanding is that I can't just delete and reattach the mailboxes since I want those mailboxes in domain2's Exchange org. 

I'm also not sure why I would need to use ADMT since the users I want the mailboxes attached to already exist in domain2 (since they're the accounts the linked mailboxes in domain1 are linked to).

You wouldn't.  My answer best matches your request.

Assuming you're correct, I'm obviously missing a step. Between deleting the linked mailbox in domain1 & attaching it to the proper user in domain2, I'm not seeing where the mailbox is actually migrated to the new Exchange server.

I thought you were just switching the user account because your question wasn't at all clear what you're trying to do.

Please post the command you're using to perform the move--the less obfuscated the better--and the complete error message you're receiving.

I figured this out. In case anyone else comes here with this issue, here's what I did.

1. Use Enable-Mailuser on the user AD objects in the target domain.

2. Use the Prepare-Moverequest.ps1 script to set the AD attributes appropriately to said users.

3. Use the New-Moverequest with the -remote switch from the target domain.

Piece of cake once you know what to do.

• Marked as answer by Carl Marshall 19 hours 31 minutes ago