If you come accross to change the name of a Domain User Account in Active Directory, its not that easy.

First, you need to change the Name in a few places. I have made a Powershellscript to help you out. download it here

Just fill out the Variables and be aware you disconnect your Exchangemailbox first, before you execute it.

After you changed the Name you maybe need to press F5 to refresh.
Make sure you reconnect the Exchangemailbox again.

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