That specific subdomain has issues with propagation: https://dnschecker.org/#A/answers.microsoft.com https://dnschecker.org/#A/answers.microsoft.com (only four

That specific subdomain has issues with propagation: https://dnschecker.org/#A/answers.microsoft.com https://dnschecker.org/#A/answers.microsoft.com (only four resolvers return records) The root zone and www. do not: https://dnschecker.org/#A/microsoft.com https://dnschecker.org/#A/microsoft.com (all resolvers return records) And querying https://www.microsoft.com/ https://www.microsoft.com/ results in HTTP 200 on the root document, but the page elements return errors (a 504 on the .css/.js documents, a 404 on some fonts, Name Not Resolved on scripts.clarity.ms, Connection Timed Out on wcpstatic.microsoft.com and mem.gfx.ms). That many different kinds of errors is actually kind of impressive. I'm gonna say this was a networking/routing issue. The CDN stayed up, but everything else non-CDN became unroutable, and different requests traveled through different paths/services, but each eventually hit the bad network path, and that's what created all the different responses. Could also have been a bad deploy or a service stopped running and there's different things trying to access that service in different ways, leading to the weird responses... but that wouldn't explain the failed DNS propagation.