Converting a mailbox type in Active Directory

After converting a Regular Mailbox or a Shared mailbox in Exchange Online.
The AD object isn’t updated back to on premise (Exchange 2010).

To convert AD object to correct mailbox type:

 

Disclaimer: All scripts and references on this blog are offered “as is” with no warranty.  These scripts are tested in my environment, it is recommended that it is tested in a test environment before using in production.