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Timeline

Every update Microsoft posted for this issue, newest first.

1. Oct 15, 2026, 20:50 CEST

   Our fix remains at 93 percent, as the remaining saturation is expected to take extra time, per process. We're continuing to monitor progress toward completion and confirm that impact is remediated for all users.

2. Oct 14, 2026, 21:33 CEST

   Our fix deployment has completed in the initial deployment rings and has started saturating in affected customers' environments. Our monitoring has validated that our fix has completed approximately 93 percent of the deployment, and we'll provide an updated timeline for it completing once it has become available.

3. Oct 13, 2026, 21:17 CEST

   Our monitoring of the deployment is ongoing as it propagates through earlier deployment rings prior to beginning saturation to affected customers’ environments. We'll provide a projected timeline for remediation based on the rate of progress as one becomes available.

4. Oct 13, 2026, 02:30 CEST

   We're continuing to monitor and track the saturation percentage of the fix deployment to ensure it reaches 100 percent in all affected environments.

5. Oct 8, 2026, 02:02 CEST

   We've validated that the previously identified recent change that removed an attribute component from the service process that requires that attribute, has led to impact. We're continuing to monitor our fix deployment; however, this process is taking longer than anticipated. The current fix saturation is at roughly 90 percent, and we'll provide a timeline of completion once it becomes available.

6. Oct 7, 2026, 01:51 CEST

   We're continuing to monitor the deployment of our fix as it progresses, and we'll aim to provide a timeline of completion by our next scheduled communications.

7. Oct 6, 2026, 01:32 CEST

   Our fix deployment is nearing completion, and most affected users should now be experiencing recovery. We’ll continue monitoring the deployment to ensure it completes and restores service for all affected users.

8. Oct 6, 2026, 01:32 CEST

   Our fix deployment is nearing completion, and most affected users should now be experiencing recovery. We’ll continue monitoring the deployment to ensure it completes and restores service for all affected users.

9. Sep 29, 2026, 01:56 CEST

   We've initialized our fix deployment to the affected environment and anticipate the impact should be fully remediated by our next scheduled update.

10. Sep 26, 2026, 02:24 CEST

    We've completed the validation of our planned fixes and are completing the final stages to prepare them for deployment. We anticipate that users will see progressive relief beginning Monday, September 28, 2026, up to our planned remediation date of Friday, October 2, 2026.

11. Sep 26, 2026, 00:33 CEST

    We're conducting verification and validation testing on our proposed remediation to ensure that it will safely and effectively remediate this issue.

12. Sep 25, 2026, 22:57 CEST

    We've identified a recent code change which we believe may be responsible for this issue and are developing a targeted fix to verify.

13. Sep 25, 2026, 18:22 CEST

    We're reviewing support case details to better understand the impact scenario and determine our next steps.

14. Sep 25, 2026, 17:56 CEST

    We're investigating a potential issue with Exchange Online and checking for impact to your organization. We'll provide an update within 30 minutes.