Microsoft 365 Shared Mailbox conversion error

Question

I use shared Mailboxes to archive terminate employees emails.

I am now getting the error below when attempting the conversion from standard to shared mailbox, any incite to the cause/resolution would be appreciated.

Error on proxy command 'Set-Mailbox -Identity:'NAMPR07A003.prod.outlook.com/Microsoft Exchange Hosted Organizations/banyanmedical.onmicrosoft.com/***UserName***' -Type:'Shared' -Confirm:$False -Force:$True' to server MWHPR17MB1488.namprd17.prod.outlook.com: Server version 15.20.4287.0000, Proxy method PSWS: Request return error with following error message: The remote server returned an error: (401) Unauthorized.. [Server=CH2PR17MB3496,RequestId=bb886dd3-188a-0a07-53af-3ea215b0bc15,TimeStamp=7/1/2021 3:33:48 PM] .

Answer 1

Same thing happened to me yesterday. I ended up assigning a license back to the user, then after confirming that the mailbox was still there for the account I went through the process of converting to a shared mailbox again and this time it worked.

I hope you were able to get yours fixed.

Answer 2

Hi Ron Kriege,

Greetings.

For us to be able to isolate the issue kindly answer the following questions.

1. How many users affected
2. How did you convert the mailbox is through Exchange admin user or powershell?
3. Please try to use a different global admin to see if the issue persist

If you previously converted mailbox through the EAC, I suggest you try to convert the user mailbox to a shared mailbox via PowerShell again to check how it works. To do this, please connect to Exchange Online PowerShell and run the cmdlet below: Set-Mailbox (ExchangePowerShell) | Microsoft Docs

Set-Mailbox *** Email address is removed for privacy *** -Type Shared

Thanks,

Linda