Status Page

O365 - Email/Outlook

2025-03-18	Status	Description
10:36 AM		Status Investigation Suspended Impacted services Exchange Online Title: Users may be experiencing issues with accessing email messages on the iOS native mail app User impact: Users may have been experiencing issues with accessing email messages on the iOS native mail app. More info: Users may have been able to click "continue" when prompted and navigate back to re-entering their password to attempt to resolve impact. If users weren't prompted but were still experiencing impact, they may have followed the steps in the following link: https://support.microsoft.com/en-us/office/reconnecting-your-microsoft-365-account-to-apple-mail-83df246e-34d2-4dbb-8e37-23a90c13e16e The problem was specific to the native mail app on iOS devices. Microsoft Outlook for mobile was not affected and could have been used without issue. Impacted users were encouraged to file a support ticket with Apple to provide valuable logging information to assist with our continued joint investigation with Apple into the source of impact. Final status: We've confirmed after monitoring service health telemetry that errors associated with impact have reduced to pre-impact thresholds as of Saturday, March 15, 2025, at 2:00 PM UTC. This confirms that the majority of users are no longer affected by this event and that additional remediation efforts within the Microsoft-managed environment aren't required. As previously mentioned, users whose impact persists should follow the steps outlined in the "More info" of this communication to remediate impact. Scope of impact: Some users accessing their email from the native iOS email app may have been affected. Start time: Monday, March 3, 2025, at 12:10 AM UTC Next steps: - We’ll continue partnering with Apple to gain root cause insights, though this is a best-effort as the underlying issue didn’t reside within the Microsoft-managed environment. - Follow the steps outlined in the “More info” of this communication in the event you’re still affected. This is the final update for the event.
10:36 AM		Status Investigation Suspended Impacted services Exchange Online Title: Users may be experiencing issues with accessing email messages on the iOS native mail app User impact: Users may have been experiencing issues with accessing email messages on the iOS native mail app. More info: Users may have been able to click "continue" when prompted and navigate back to re-entering their password to attempt to resolve impact. If users weren't prompted but were still experiencing impact, they may have followed the steps in the following link: https://support.microsoft.com/en-us/office/reconnecting-your-microsoft-365-account-to-apple-mail-83df246e-34d2-4dbb-8e37-23a90c13e16e The problem was specific to the native mail app on iOS devices. Microsoft Outlook for mobile was not affected and could have been used without issue. Impacted users were encouraged to file a support ticket with Apple to provide valuable logging information to assist with our continued joint investigation with Apple into the source of impact. Final status: We've confirmed after monitoring service health telemetry that errors associated with impact have reduced to pre-impact thresholds as of Saturday, March 15, 2025, at 2:00 PM UTC. This confirms that the majority of users are no longer affected by this event and that additional remediation efforts within the Microsoft-managed environment aren't required. As previously mentioned, users whose impact persists should follow the steps outlined in the "More info" of this communication to remediate impact. Scope of impact: Some users accessing their email from the native iOS email app may have been affected. Start time: Monday, March 3, 2025, at 12:10 AM UTC Next steps: - We’ll continue partnering with Apple to gain root cause insights, though this is a best-effort as the underlying issue didn’t reside within the Microsoft-managed environment. - Follow the steps outlined in the “More info” of this communication in the event you’re still affected. This is the final update for the event.

2025-03-14	Status	Description
10:29 AM		Status Service Degradation Impacted services Exchange Online Title: Some users may encounter Non-Delivery Report (NDR) failures when sending or receiving email messages User impact: Some users may encounter NDR failures when sending or receiving email messages in Exchange Online. More info: Users may receive a Non-Delivery Report (NDR) containing an error stating "554 5.6.0 Corrupt message content". Current status: We've identified that impact is not limited to users sending IRM protected email as we previously communicated. We've updated the title, user impact, more info and scope of impact sections of this communication to reflect that new information. Our previously stated fix will continue deploying to affected infrastructure while we continue monitoring its efficacy as it progresses. Concurrently, we’ve shifted attention to our reproduction efforts and deeper log analysis to further isolate the cause of impact and identify new mitigation strategies. Scope of impact: Some users serviced by the impacted portion of infrastructure sending or receiving email in Exchange Online may be affected, although impact is limited to a small subset of messages. Next update by: Friday, March 14, 2025, at 6:30 PM UTC
10:24 AM		Status Service Restored Impacted services Exchange Online Title: Some users may see add-ins in Outlook desktop and Outlook on the web that aren't installed or removable User impact: Users may have seen add-ins in Outlook desktop and Outlook on the web that weren't installed or removable. More info: As a temporary workaround, affected users could have disabled ‘Show Apps in Outlook’ for relief, but this only applied to classic Outlook on Windows. There was no workaround for Outlook on the web, new Outlook on Windows, or Outlook for Mac. Final status: Following the deployment of our fix, our internal tests and validations from affected users have confirmed that the code problems have been addressed, and that impact has been remediated. Scope of impact: Some users may have seen add-ins in the Outlook desktop client and Outlook on the web which weren't installed and couldn't be removed. Start time: Thursday, January 9, 2025, at 8:36 PM UTC End time: Thursday, March 13, 2025, at 8:15 PM UTC Root cause: A service update to a portion of service infrastructure that facilitates identification of which add-ins are enabled for users in Outlook on the web and the Outlook desktop client contained an impacting code issue. Next steps: - We're further analyzing the offending service update so we can help identify similar issues during our pre-deployment testing and validation processes. This is the final update for the event.
10:16 AM		Status Service Restored Impacted services Exchange Online Title: Users may encounter delays or failures when sending or receiving email messages in Exchange Online User impact: Users may have encountered delays or failures when sending or receiving email messages in Exchange Online. Final status: We've identified that the remaining impact relates to a separate issue which exhibits a nearly identical impact to users. We've confirmed that our fix completed in the affected environment and impact for this issue is remediated based on our internal monitoring. We'll continue investigating the root cause of the remaining impact and supplying further updates in EX1030895. Scope of impact: Any user serviced by the impacted portion of infrastructure sending or receiving some email in Exchange Online may have been affected. Start time: Friday, March 7, 2025, at 5:30 PM UTC End time: Thursday, March 13, 2025, at 5:00 PM UTC Root cause: A recent service update, intended to improve our message transport services, introduced a code issue that resulted in impact for a portion of service infrastructure. Next steps: - We're reviewing our service update validation procedures to detect and prevent similar issues from occurring in the future. This is the final update for the event.