It is no longer possible to set the WindowsEmailAddress property on a synchronized user

If you are an Office 365 user, you may have come across certain workarounds and "gotchas" over the years. One such workaround was the use of the -WindowsEmailAddress parameter in the Set-Mailbox cmdlet. This parameter was used to set the WindowsEmailAddress property for synchronized users. However, as of now, it is no longer possible to use this parameter for synchronized users.

This change has been brought about by Microsoft in order to simplify and streamline the process of managing user accounts in Office 365. While it may require some adjustments in your current workflows, this change ultimately aims to provide a more user-friendly experience and reduce the likelihood of errors.

To learn more about this change, including the implications it may have for your Office 365 setup, check out the original article by Michael Van Horenbeeck here.