NuPoint UM to O365 Issues

[ralph]

Are there any known issues with the NuPoint and O365?
Our system has stopped UM integration. Voicemails are no longer being sent to emails.
Wireshark shows it connecting and then dropping as soon as it connects.  It never gets to the point of trying to authenticate.
We

[sarond]

Hi Ralph,

Yes, there is a known issue, If you have access to Mitel KMS article is SO8515.

There is a patch needed.

It appears that Microsoft made a change in the access token response between Microsoft and MSL. Extra characters were added and they caused the Nupoint to overflow its access token buffer and report an empty or bad token and abort the transaction. This started to occur the first week in May 2025. Microsoft typically roll out their changes over time so not all sites were effected at once but now Mitel has been inundated with calls reporting that the Advanced UM feature had stopped working. Once the root cause was established Mitel have a patch to resolve this.