Name must be unique per owning mailbox. There’s already a request with the name

While migrating some public folders to Office 365 Groups, I kept running into issues with one of the target groups:

“De gebruiker XXX heeft al een aanvraag die in behandeling is. Verwijder de bestaande aanvraag en hervat de huidige batch of start een nieuwe batch voor deze gebruiker. –> Name must be unique per owning mailbox. T”

In english you’ll probably see “Name must be unique per owning mailbox. There’s already a request with the name “.

I figured there was a moverequest hanging / not properly cleaned up; but none to be found with get-moverequest, get-migrationuser or get-migrationbatch; all clean!

In the end, it took almost 2 weeks of patience after contacting support until the Exchange Online backend team reset a hanging job on their end. So if you google above errors and come here, check if you have double jobs, if you don’t, request support and make sure they escalate to the product team immediately.

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3 years ago

Hi! I had the same problem and could fix it with two options: 1- Select the users with the problem, remove them from the batch and create a new batch with him in it. The process will restart the “sync” parameter of the user on O365 and mails will download normally. 2- Clean the sync status of the user using the following command: Get-MigrationUser -BatchId YOURBATCHIDNAME | Get-MigrationUserStatistics | Where-Object {$_.status -eq ‘failed’} | Get-SyncRequest | Remove-SyncRequest In some cases, the second solution was enough, as I had 8k users migrating and 20% of them with failure, I rather create… Read more »