Microsoft's Exchange Admin Center (EAC) became inaccessible to administrators on October 12 after a configuration change produced unexpected HTTP responses. Admins trying to reach the web-based management console were greeted with an "Internal Server Error" and, according to Microsoft's incident updates, anomalous 302 redirects. No workaround was initially available, leaving European users with a disrupted morning.
Microsoft acknowledged the issue around 0937 UTC and spent more than two hours analyzing logs before testing a rollback. That rollback proved effective: by the final update, the company said reverting the identified change had "restored expected service functionality." Microsoft also pledged to review both the change and its monitoring and telemetry to improve detection of similar behavior.
But as The Register notes, this is a familiar cycle. In September, a configuration change broke SharePoint Online pages; in April, a similar tweak knocked out Outlook for iOS; and in 2025, a Microsoft 365 outage was also blamed on a configuration change. The EAC incident was resolved before the end of the working day, with a preliminary Post-Incident Report due within two business days and a final report expected the following week.