Scenario: You need to remove a user’s photo in Exchange. You have verified that the thumbprintphoto attribute is <not set> in Active Directory, but the photo is still showing in Exchange.
Cause: The mailbox stores a high-resolution photo in the mailbox in additional to the photo that is stored in AD. You will need to remove it from the mailbox.
Solution: Run the following PowerShell command to remove the photo for testuserA.