Users were intermittently unable to access their calendars in Outlook on the web and the new Outlook desktop client

Title: Users were intermittently unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users were intermittently unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Impacted users may have received the following error message: “Can’t retrieve calendar events right now. Refresh the browser and try again.” As a workaround, some impacted users were able to access their calendar in the classic Outlook desktop client. Final status: We’ve completed deployment of the fix to the affected environment and monitoring has confirmed that the impact is resolved. Additionally, a subset of affected users has confirmed that the issue is resolved. Scope of impact: Some users attempting to access their calendars through Outlook on the web or the new Outlook desktop client may have been intermittently impacted. Start time: Wednesday, July 1, 2026, at 2:49 PM UTC End time: Saturday, October 17, 2026, at 12:33 AM UTC Root cause: A caching issue caused outdated calendar data to be referenced after the calendar folder information was refreshed, resulting in intermittent calendar access failures. Next steps: - We’re reviewing this event to identify opportunities to prevent similar impact from recurring. This is the final update for the event. This is the final update for the event.

Title: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Impacted users may receive the following error message: “Can’t retrieve calendar events right now. Refresh the browser and try again.” As a workaround, impacted users can access their calendar in the classic Outlook desktop client. Current status: We’ve completed deployment of the fix to the initially affected service environment and expect this has remediated impact for users in that environment. The fix is continuing to propagate across the remaining affected environment, with this process expected to take approximately one additional week to complete. We’ll continue monitoring the deployment as it progresses to confirm that impact is fully remediated. Scope of impact: Some users attempting to access their calendars through Outlook on the web or the new Outlook desktop client may intermittently be impacted. Start time: Tuesday, July 7, 2026, at 5:33 PM UTC Root cause: The issue is related to the calendar cache state following a refresh, where the event-loading process may continue referencing outdated calendar data after the folder information is updated. Next update by: Monday, October 19, 2026, at 10:00 AM UTC

Title: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Impacted users may receive the following error message: “Can’t retrieve calendar events right now. Refresh the browser and try again.” As a workaround, impacted users can access their calendar in the classic Outlook desktop client or through Microsoft Teams. Current status: Our fix deployment is completing for the initially identified service environment; however, we’ve confirmed that additional environments remain impacted. While some users should experience impact resolution as the fix reaches them, we’re extending the fix deployment to the remaining affected environments, and we’ll provide an estimation for its completion once available. Scope of impact: Some users attempting to access their calendars through Outlook on the web or the new Outlook desktop client may intermittently be impacted. Estimated time to resolve: Friday October 9, 2026 Root cause: The issue is related to the calendar cache state following a refresh, where the event-loading process may continue referencing outdated calendar data after the folder information is updated. Next update by: Monday, October 12, 2026, at 9:30 AM UTC

Title: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Impacted users may receive the following error message: “Can’t retrieve calendar events right now. Refresh the browser and try again.” As a workaround, impacted users can access their calendar in the classic Outlook desktop client or through Microsoft Teams. Current status: Our fix deployment is completing and we're reaching out to some users to confirm the issue is no longer occurring. Scope of impact: Some users attempting to access their calendars through Outlook on the web or the new Outlook desktop client may intermittently be impacted. Estimated time to resolve: Friday October 9, 2026 Root cause: The issue is related to the calendar cache state following a refresh, where the event-loading process may continue referencing outdated calendar data after the folder information is updated. Next update by: Monday, October 12, 2026, at 7:00 AM UTC

Title: Users may be intermittently unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users may be intermittently unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Impacted users may receive the following error message: “Can’t retrieve calendar events right now. Refresh the browser and try again.” As a workaround, impacted users can access their calendar in the classic Outlook desktop client or through Microsoft Teams. Current status: We’ve identified that the issue is related to the calendar cache state following a refresh, where the event-loading process may continue referencing outdated calendar data after the folder information is updated. We’ve implemented and merged a fix to ensure the refreshed calendar data is correctly used when loading subsequent events. The fix is expected to reach affected users by October 9, 2026. Scope of impact: Some users attempting to access their calendars through Outlook on the web or the new Outlook desktop client may intermittently be impacted. Estimated time to resolve: Friday October 9, 2026 Root cause: The issue is related to the calendar cache state following a refresh, where the event-loading process may continue referencing outdated calendar data after the folder information is updated. Next update by: Friday, October 9, 2026, at 5:30 PM UTC

Title: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Users get the error message, “Can’t retrieve calendar events right now. Refresh the browser and try again.” Users can work around this issue by accessing their calendar in classic Outlook or through Microsoft Teams. Current status: We’re continuing to review service health telemetry and HAR logs to investigate what we suspect is a caching issue that’s leading to the impact. We’re also testing potential solutions to confirm our findings and determine our next steps. Scope of impact: Some users that attempt to access their calendars through Outlook on the web and new Outlook may be intermittently affected.

Title: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Users get the error message, “Can’t retrieve calendar events right now. Refresh the browser and try again.” Users can work around this issue by accessing their calendar in classic Outlook or through Microsoft Teams. Current status: Our review of service health telemetry and the HAR logs persists as we continue to isolate the source of this issue. Scope of impact: Some users that attempt to access their calendars through Outlook on the web and new Outlook may be intermittently affected. Next update by: Thursday, October 1, 2026, at 7:30 AM UTC

Title: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Users get the error message, “Can’t retrieve calendar events right now. Refresh the browser and try again.” Users can work around this issue by accessing their calendar in classic Outlook or through Microsoft Teams. Current status: We're currently reviewing telemetry and HTTP Archive format (HAR) log information as we investigate the cause of impact. Scope of impact: Some users that attempt to access their calendars through Outlook on the web and new Outlook may be intermittently affected. Next update by: Wednesday, September 30, 2026, at 6:30 PM UTC

Title: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client User impact: Users may intermittently be unable to access their calendars in Outlook on the web and the new Outlook desktop client. More info: Users get the error message, “Can’t retrieve calendar events right now. Refresh the browser and try again.” Current status: We're investigating a potential issue with Exchange Online and checking for impact to your organization. We'll provide an update within 30 minutes.