Hi from the team at Symprex!

Following the implementation of NAA authentication by Microsoft in February, we are seeing the disabling of legacy tokens on increasing numbers of customer Microsoft 365 tenants - this process is expected to be completed my Microsoft in June.

A very large percentage of customers have already completed the upgrade to the latest version of the add-in which we detailed in February. If you are already on v3, or joined Signature 365 after February, no action is required.

If the decision was made to enable legacy tokens and delay the upgrade, its is of utmost importance that the process is now completed and the upgrade is applied. Once legacy tokens are fully disabled, the previous versions of the add-in cannot function, and users with the Outlook add-in will not receive signatures until this is completed.

Details on the update process are noted here: Nested app authentication (NAA) and deprecation of Exchange legacy tokens


If you have any questions on the process, please contact our support team.