Traditionally, signatures were stored locally on a user's Windows device and if a user wanted to have their signature be the same on different devices, they had to recreate the signature on each device.
Outlook for Windows is introducing e-mail signatures that will be stored in the cloud rather than being stored locally on the user’s Windows device. With this feature, signatures will now be associated with an email account and they will be available on all devices where that account is configured. The change is scheduled to roll out to Microsoft 365 Monthly Channel, Targeted, in late July, 2020 and to the Monthly Channel, Production, in late August, 2020.
This means that accounts hosted on Exchange on-premises servers, with third-party email services, or utilizing POP/IMAP accounts will not be able to roam their signatures at this time.
To this problem, Outlook has created a registry value Microsoft 365 tenants or signature add-in vendors can create to prevent migration of signatures and temporarily disable the feature. The path to the registry value is:
This is a DWORD value and setting it to 1 will disable the feature and prevent signature migration upon rollout. Device administrators can choose to use its corresponding Group Policy location to the same effect:
This value is temporary and will be deprecated once an API is published allowing software vendors and administrators to set the value of signatures. Sufficient time will be given to allow for the changes to happen.
For more information, please refer to this article.
Applies to: All versions of MC
Reference: TFS # 240286
Knowledge base ID: 0292
Last updated: Jul 16, 2020