Security News > 2023 > April > New Microsoft 365 outage causes Exchange Online connectivity issues

Microsoft is investigating ongoing Microsoft 365 issues preventing some Exchange Online customers from accessing their mailboxes.
According to outage monitoring platform Downdetector, thousands of Microsoft 365 report experiencing server connection and login issues, as well as when accessing their Outlook mailboxes.
Microsoft says these Exchange Online connectivity problems only affect North American users.
While the company added that more info on this outage can be in the Microsoft 365 admin center under EX546390, the advisory only says that Microsoft is "Looking into a potential problem" and the "Potential end-user impact."
Yesterday, Microsoft addressed more Microsoft 365 issues preventing some users from searching assets across multiple services, including but not limited to Outlook on the Web, Exchange Online, SharePoint Online, Microsoft Teams, and Outlook desktop clients.
A massive outage also hit Microsoft 365 in January after router packet forwarding issues within Microsoft's Wide Area Network were inadvertently triggered by a router IP address update.
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