By Guru Baran
Publication Date: 2025-12-02 13:38:00
Microsoft is currently investigating a service disruption affecting the Microsoft Defender portal, which has blocked numerous security professionals from accessing critical threat management tools.
The issue, tracked under the identifier DZ1191468 in the Microsoft 365 admin center, sparked concerns early Tuesday as administrators reported timeouts and login failures when attempting to load the security dashboard.
The disruption began earlier today, with users across multiple regions experiencing difficulties reaching the Defender portal (security.microsoft.com). According to Microsoft’s status updates, the root cause has been linked to an unexpected “spike in traffic” that overwhelmed the service’s access capabilities.
