Security News > 2021 > April > Exchange Online down: Microsoft 365 outage affects email delivery
A Microsoft 365 outage is preventing Exchange Online users from sending and receiving emails, with messages being stuck in transit and not reaching the recipients' inboxes.
"We're investigating a potential issue with Exchange Online mailflow in North America," Microsoft shared on the company's Microsoft 365 Status Twitter account.
The Microsoft 365 Service health status page is currently directing customers to the Microsoft 365 Status Twitter account for more insight regarding this incident.
Office 365 users report seeing "Temporary server error. Please try again later" MX errors and experiencing SMTP issues across Microsoft 365 tenants.
Last month's massive outage impacted multiple other Microsoft services at the time besides Exchange Online, including Microsoft Teams, Forms, Xbox Live, Intune, Outlook.com, Office Web, SharePoint Online, OneDrive for Business, Yammer, and more.
In September, Microsoft customers experienced another worldwide outage showing "Transient" errors and knocking down Office 365 and related services, including Microsoft Teams, Office.com, Power Platform, and Dynamics365.
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