Menu Close

[Quick Fix] How To Solve Mailbox Exists On-premise And Office 365?

The strategies in this post help you on how to solve mailbox exists on-premise and office 365.

Here is the sample user who has a mailbox in on-premise.

How to solve mailbox exists on-premise and office 365

The same user also has a mailbox in cloud.

office 365 mailbox

There are a couple of options to get rid of the issue. Let’s discuss each options.

Option 1: Remove Exchange Online License

  • Go to Microsoft 365 Admin Center
  • Remove the Exchange online license
  • After removed the license, the account will appear as a mail user in cloud.
microsoft office 365
  • Now, the mailbox in on-premises needs to be migrated to Exchange online and assign the necessary license.
  • Once the mailbox appears ok in Microsoft 365, perform the mailbox restore request to move mailbox contents from the soft-deleted mailbox to the active mailbox.

New-MailboxRestoreRequest -SourceMailbox “Softmailbox@techieberry.com” -TargetMailbox “Activemailbox@techieberry.com” -AllowLegacyDNMismatch

outlook office 365

Option 2: Delete the Azure Active Directory account

  • As you are aware, exchange online mailbox is associated to an Azure Active Directory account.
  • Connect to Azure powershell (Connect-Msolservice)
  • Remove the user account. Remove-MsolUser -UserPrincipalName test248@techieberry.com -Force
  • After the account is removed, the mailbox in cloud will be moved to soft-deleted. It will not appears in the active users list.
mailbox exists on-premise and office 365
  • After sync is complete, the on-premises account will sync to Azure Active Directory again as a mail user.
solve mailbox exists on premise and office 365
  • Now, you need to migrate the migrate the on-premises mailbox to Exchange Online and assign the appropriate license.
  • Once it is done, perform the mailbox restore request to move mailbox contents data from the soft-deleted mailbox to the active mailbox.

For more information about mailbox exists on-premises and office 365, check the Microsoft website.

Want to improve your Exchange Online experience for better productivity? Check out the tips and tricks mentioned here.

Now I’d like to hear from you:

Which options from today’s post are you going to try first? Or maybe you have a question about something that I covered.

Either way, let me know by leaving a comment below right now.

Related Posts

Leave a Reply

Your email address will not be published. Required fields are marked *