How to move Mailboxes over from old Exchange 2007 to new EBS 2008 network?

This q is similar to: How to move Exchange 2003 mailbox or store from 2003 to 2007 on separate networks?

Basically I am trying to move our exchange mailboxes over to a test domain that is hosting EBS2008 with Exchange 2007. We plan to move as soon as we can when we have our exchange data over.

I have tried moving a db with mailboxes over but cannot get it to mount in the new Exchange in any way possible, including mounting it onto a recovery store. From my understanding the ONLY prerequisite for moving Exchange DBs across is that it must have the same Organizational name (unlike previous versions of Exchange). If anyone has any insight as to why I cannot mount and simply reattach the mailboxes, please give me an idea as to what could be wrong. It should be as simple as this. Note that the DBs I have are in a clean state.

I cannot use ExMerge because I am not running any mailboxes on 2003.

I have also tried using a 32bit Vista machine with the Export-Mailbox cmdlet to extract mailboxes but anything I do to it results in Permission errors. I have tried to troubleshoot these with no success. I am running in full admin with proper exchange roles and yet it still gives me access denied errors:

Export-Mailbox : MapiExceptionNetworkError: Unable to make admin interface conn
ection to server. (hr=0x80040115, ec=-2147221227)

Also some errors show in the management console:

get-MailboxDatabase
Completed
Warning:
ERROR: Could not connect to the Microsoft Exchange Information Store service on server TATOOINE.baytech.local. One of the following problems may be occurring: 1- The Microsoft Exchange Information Store service is not running. 2- There is no network connectivity to server TATOOINE.baytech.local. 3- You do not have sufficient permissions to perform this command. The following permissions are required to perform this command: Exchange View-Only Administrator and local administrators group for the target server. 4- Credentials have been cached for an unpriviledged user. Try removing the entry for this server from Stored User Names and Passwords.

Why I have to use a 32bit machine to export a simple .pst file is beyond me...

So yeah I am now out of ideas and any help would be great! Thanks in advance.

I would suggest using the commandlet Export-Mailbox, as you described. There is an article on the MS Exchange Team Blog that goes over its usage and discusses the permissions needed. (There is a newer post as well that is more clear)

Since I have found their post to be somewhat vague on setting the correct permissions, I prefer the instructions in an alternate post, which show how to give yourself permissions on all accounts or only on an individual account (my preferred method when I only have to export a few accounts). Basically, before running the export command, you run:

Add-MailboxPermission –Identitiy “MailAlias” –User Username –AccessRight FullAccess

where "MailAlias" is the account you are trying to export, and Username is your account (or the account you will be running mailbox-export as). After that, export away:

Export-Mailbox –Identity <mailboxUser> -PSTFolderPath <pathToSavePST>

Lastly, to be clean, I like to remove the permissions and return things their original state, so:

Remove-MailboxPermission –Identitiy “MailAlias” –User Username –AccessRight FullAccess

After that, you are all set, you can take those PST's over to your new server, and import them. (You will probably need to grant yourself FullAccess to the new mailbox in order to run the import)

As an aside, the reason you need to run the pst export on a 32-bit machine is that the export has a dependency on Outlook, which is currently only 32-bit (this is described in the second posting from the MS Exchange Blog). I recall somewhere that MS was planning on correcting this limitation with the release of Office 2010.