Microsoft email outage hits Toronto hospitals and City services, still ongoing
Unity Health Toronto declared a Code Grey on November 12 after losing reliable email access during a global Microsoft 365 outage. Patient care was not affected, but the disruption continued into November 13.
Reported. A news outlet found this. voche.me names the outlet and links its report. Read the original report on cp24.com.
A global Microsoft 365 outage on November 12 caused Unity Health Toronto to declare a Code Grey, the hospital network's protocol for a loss of infrastructure, as staff lost reliable access to email and other Microsoft communication tools. The disruption continued into November 13 with no confirmed end time.
What happened
CP24 reported that Unity Health Toronto, which operates St. Michael's Hospital, activated Code Grey on November 12 after staff experienced difficulties sending and receiving email. University Health Network and Sunnybrook Hospital also reported that email was temporarily unavailable. At peak, nearly 150,000 Outlook error reports were filed globally at 1:30 pm Eastern.
The City of Toronto warned on November 12 that some City services may be temporarily unavailable or experience delays. The University of Toronto, Seneca Polytechnic and George Brown Polytechnic also reported disruptions. VIA Rail said passengers could not receive email updates about their trips.
Patient care not affected
All three hospital networks stated clearly that patient and resident care was not affected. Unity Health Toronto said in a statement that "our hospitals remain safe and open to provide care." University Health Network and Sunnybrook gave the same assurance, CP24 reported.
What residents can do
Residents with urgent questions about hospital appointments or procedures should call the hospital's main telephone line rather than send email while the disruption continues. Each hospital's direct phone numbers are on its own website.
Status as of November 13
Microsoft said it had applied patches, restarted servers and rerouted traffic, and was seeing improvements in mailbox access. The company warned that some intermittent problems could continue and gave no confirmed end time. No statement from Unity Health confirming the Code Grey had been lifted was available as of the morning of November 13.
Toronto residents can check the websites of Unity Health Toronto, University Health Network and Sunnybrook for updates on service availability.
Questions this story answers
Which Toronto hospitals were affected by the Microsoft outage on November 12?
CP24 reported that Unity Health Toronto, which operates St. Michael's Hospital, declared a Code Grey on November 12 after staff lost reliable access to email and other Microsoft 365 tools. University Health Network and Sunnybrook Hospital also reported that staff were unable to send or receive email. Code Grey is activated when there is a loss or failure of infrastructure.
Was patient care affected at Toronto hospitals during the Microsoft outage?
No. Unity Health Toronto stated directly that patient and resident care was not affected by the outage and that its hospitals remained safe and open to provide care. University Health Network and Sunnybrook gave the same assurance, according to CP24's November 12 report. The disruption was limited to staff communication tools, primarily email.
What should Toronto residents do if they have an urgent hospital appointment question?
CP24 reported on November 12 that residents with urgent appointment inquiries should contact hospital main telephone lines rather than email during the outage. The disruption continued into November 13 with no confirmed end time from Microsoft. Check the website of your hospital or clinic for direct phone numbers.
What other Toronto services were disrupted by the Microsoft outage?
CP24 reported that the City of Toronto warned some of its services may be temporarily unavailable or experience delays. The University of Toronto, Seneca Polytechnic and George Brown Polytechnic also reported disruptions. VIA Rail said passengers were unable to receive email communications about their trips.
What caused the Microsoft 365 outage and when will it be fixed?
Microsoft reported that a portion of its infrastructure experienced elevated load across multiple regions, causing connectivity errors. At peak, nearly 150,000 Outlook reports came in at 1:30 pm Eastern on November 12. Microsoft said recovery actions including patches, server restarts and traffic rerouting were applied and improvements in mailbox access were being seen, but warned some intermittent problems could continue. No confirmed timeline for full restoration was given as of the morning of November 13.
What is a Code Grey in a hospital?
A Code Grey is an internal emergency declaration activated when a hospital loses or suffers a failure of critical infrastructure, such as power, water or in this case a key communication system. CP24 reported that Unity Health Toronto declared Code Grey after losing reliable access to Microsoft email and other tools. It signals staff to follow backup procedures while the problem is resolved.
Is the Microsoft outage now resolved in Toronto?
As of the morning of November 13, the outage had not been fully resolved. Microsoft said improvements were being seen but warned that intermittent problems could continue, with no confirmed end time. No statement from Unity Health confirming that the Code Grey had been lifted was available. Residents should check the websites of affected institutions for updates or call directly.
Who made decisions about the hospital response to the outage?
Unity Health Toronto's own management activated the Code Grey protocol, as CP24 reported on November 12. No City Council vote or decision was involved. For City of Toronto decisions related to hospital services and community health, follow the new City Council's work at the promise tracker at /on/toronto-2026/tracker.
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