Microsoft 365 Alert – Service Degradation – Microsoft Teams – Some users can’t edit the start and end time of Microsoft Teams webinars that were created before Daylight Saving Time – RESOLVED

Announcements Sourav Nandi

05/04/2023 09:10:00 AM (GMT)

NHSmail Reference : INC35164757

Microsoft Reference : TM537286

Issue Status : RESOLVED

Issue Description : Users can’t edit the start and end time of Microsoft Teams webinars that were created before Daylight Saving Time.

More Information : As a temporary solution, users can change their time zone, edit the start time and end time of the affected webinars, and then revert back to the original time zone.

Final Update : 10/04/2023 08:32:00 AM – The fix has finished deploying and Microsoft have monitored telemetry to confirm the impact is resolved.

Scope of impact : Your organization is impacted, and a small number of users can”t edit the start and end time of Microsoft Teams webinars that were created before Daylight Saving Time.

Root cause : Daylight Saving Time triggered a latent code issue that’s causing non-compliant data to be sent when webinar times are updated, resulting in 400 errors.

Next steps : To help prevent similar impact in the future, Microsoft are further reviewing the latent code issue and how it was introduced.