If an Office 365 tenant goes to the bother of creating nice OWA autosignatures for users, shouldn’t we also removed the ability to edit the signatures in OWA settings? RBAC seems like the right way to do the job, but in this case, the way RBAC restricts options by removing the right to run cmdlets or parameters means that the block affects other OWA settings. Fortunately, the Exchange developers thought of this and provide an option in OWA mailbox policies to save the day.
OWA stores user signatures in mailboxes, which makes it a lot easier for Office 365 admins to update signatures centrally with just a few lines of PowerShell and some HTML magic. OK, maybe more than a few lines… but it’s a lot less complicated than it is to mess around with the system registry and points the way to how Microsoft might introduce cloud signatures for all Outlook clients.