I was recently attempting to run a mailbox export request to a PST file in Exchange 2010 Service Pack 3, on running the New-MailboxExportRequest cmdlet, I was presented with the following error message:
The term "New-MailboxExportRequest" is not recognized.
In order to resolve this issue I had to grant the account performing the export request the ‘Import Export Mailbox’ role assignment as below.
New-ManagementRoleAssignment –Role “Mailbox Import Export” –User "DOMAIN\USER"
Once I restarted my powershell session, I was able to succesfully run the New-MailboxExportRequest cmdlet.
Deans Blog 
Thanks for that. Had the exact same problem trying to export a mailbox to .pst. I ran your command now it’s all working fine.
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Glad to be of help…
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Great work and thanks for elaborated step
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Thanks for your great TIP
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Not a problem, glad to be of help…
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Very helpful. Thanks!
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2+ years later and your post is still helping people! Thank you.
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This saved me big time when having to export old mailboxes to PST’s when our Exchange server went down.
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Thanks a lot!
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This is very helpful, but I’m looking for a slightly different version. Can New-ExportMailboxRequest be used to export data to a CSV file? Or only PST? I’m trying to export the Contacts folder for all of the users on one small Exchange 2010 SP3 server to CSV files (preferably each user would have their own file, but it could work in one file as long as the output was tagged so I know whose mailbox they came from).
Thanks,
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I had been searching everywhere to get this solved, and couldn’t find anything. This ended up being the fix. Thank you!
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Very helpful….Just restarted Powershell. Problem Resolved
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