Microsoft 365 Alert – Service Degradation – Microsoft 365 Defender – Users may be unable to sign into the Microsoft 365 Defender portal – RESOLVED

22/05/2023 09:00:00 AM (GMT)

NHSmail Reference : INC35976434

Microsoft Reference : DZ558899

Issue Status : RESOLVED

Issue Description : Users may be unable to sign into the Microsoft 365 Defender portal.

More Info : Users may be unable to sign into the Microsoft 365 Defender portal.

Final Update : 22/05/2023 10:20:00 AM – Following Microsoft’s analysis of trends in service telemetry, they’ve determined that a portion of infrastructure responsible for regulating Microsoft 365 Defender portal access was unexpectedly operating below acceptable performance thresholds. They’ve successful restarted the affected infrastructure, and confirmed after a monitoring period that impact has been remediated.

Scope of impact : Impact is specific to some users who are served through the affected infrastructure in the United Kingdom.

Root cause : A portion of infrastructure, responsible for regulating Microsoft 365 Defender portal access, was unexpectedly operating below acceptable performance thresholds.

Next steps : Microsoft are analyzing performance data and trends on the affected systems to help prevent this problem from happening again.