In Exchange I checked the Manage Full Access Permission settings and found the "OurDomain\EXCHMB01$" missing. I attempted to add it via Powershell but it does not appear when I view the Manage Full Access Permission dialog window. When I run get-mailbox I see the entry with IsInherited = False. On other accounts this is set to true. I have not been able to find the syntax to set this.
More importantly I am not sure how to proceed to enable this account log in function.