Microsoft 365 status

How we check Microsoft 365

We watch outlook.office.com from all five of our probe regions, every 2 minutes. A region that sees a failure does not make this page say "down" on its own: a second region has to agree first, the same confirmation rule every YoPingMe monitor uses.

We watch the web host that Outlook and the core Office apps are served from, and pin the response an anonymous request receives rather than assuming a 2xx. Microsoft 365 is a large bundle of separately operated services, so a reading of the mail and document apps most people mean by "Microsoft 365" is more direct than a page describing the whole suite.

What is Microsoft 365?

Microsoft 365 bundles Outlook, Word, Excel, Teams, and a long list of other services under one subscription and one admin experience, sold to individuals and to organisations of every size. That bundling is convenient day to day and makes "is Microsoft 365 down" a genuinely ambiguous question, since the suite rarely fails as a single unit and almost never fails identically for every organisation using it.

Outlook and the core Office web apps are the services this page watches, because they are what most people actually mean when they ask about Microsoft 365 being down, even though the brand covers far more than mail and documents. A reading against those apps says nothing definitive about Teams, SharePoint, or any of the other services bundled under the same subscription, each of which can have its own incident independent of the others.

Organisational configuration is the most common source of what looks like an outage and is not one. Conditional access policies, custom domain mail routing, and licensing assignments are all set per tenant, and a change to any of them, deliberate or accidental, can make Microsoft 365 unreachable for one organisation while the platform serves everyone else normally. An expired certificate on a custom mail connector or a conditional access rule tightened during unrelated security work both produce failures that look exactly like a platform incident and have nothing to do with one.

Delivered mail is worth separating from reachability when thinking about what an outage actually puts at risk. A period where Outlook cannot be reached does not affect messages already stored, and the practical question afterwards is whether mail sent to your organisation during the window queued elsewhere and retried successfully rather than being lost, which server logs answer far better than assumption in either direction.

Re-authentication prompts are a frequent source of confusion that has nothing to do with availability. Conditional access can require signing in again after a new device, an unfamiliar location, or a policy update, independent of whether the underlying services are running normally. Completing that challenge is a security control functioning as intended, not a sign that anything is actually down, and it is worth ruling out before treating a login prompt as evidence of an incident.

Frequently asked questions

Is Microsoft 365 down right now?

Check the board above; it reflects our own probes against Outlook and the core Office web apps from all five of our regions, refreshed every couple of minutes. Microsoft 365 bundles many separate services, so this is a reading of the ones most people mean, not every component Microsoft operates under that name.

My organisation's Microsoft 365 is unreachable but this page shows it up. What should I check?

Check the Microsoft 365 admin center's own service health page for your tenant, because incidents are frequently scoped to a specific service, region, or even a single tenant configuration rather than the whole platform. A conditional access policy, an expired certificate on custom domain mail routing, or a licensing change will all produce an outage-shaped failure for your organisation while Microsoft 365 broadly reports healthy.

Does an Outlook outage affect email already delivered?

No. An outage affects reachability going forward, not mail that already arrived and was stored. What is worth checking after any incident is whether messages sent to your organisation during the outage window queued and retried successfully, which mail server logs settle more reliably than assuming either the best or the worst.

Is the Microsoft 365 admin center service health page the same as this one?

No. That page reports what Microsoft has confirmed internally, scoped to your own tenant and licensed services, which is more relevant to your organisation than any outside probe could be. This page reports what our own probes measured against the public web apps, from outside Microsoft's infrastructure, on a fixed schedule, whether or not Microsoft has posted an update yet.

I am locked out and being asked to re-authenticate. Does that mean something is down?

Usually not. Conditional access policies can require re-authentication after a new device, a location change, or a security policy update, entirely independent of whether Microsoft 365's services are healthy. Completing the sign-in challenge resolves it; it is a security control working as designed, not a symptom of downtime.