Hi, I'm Diane and I'm happy to help you today.
What OS are you using?
What browser do you use? Did you try using Firefox? Users receiving this error message in Edge or Chrome report Firefox works with outlook.com.
We're not sure if the problem is a bug in chromium-based browsers or the result of upcoming changes.
Microsoft is ending support for older browser versions and older operating systems connecting to outlook.com. It was my understanding this would take effect later this year. I'm checking with support to find out if it is effect now or if there is a different issue causing that error message.
We understand the importance of accessing your account Outlook.com from anywhere. Many customers access Outlook.com from web browsers. While most customers access their personal email accounts through modern and current browsers, we offered a lightweight version of the Outlook web app that was supported by older browsers. As we accelerate our security efforts to better protect our customers, we are retiring the lightweight version of the Outlook web app. This means that after 2024, customers will need to run the latest versions of a supported browser to run Outlook.com.
Minimum system requirements to run Outlook.com browser: Microsoft Edge (version 79 or later) Chrome (version 79 or later) Firefox (78 or later) Safari (version 16 or later) Opera (76 years or later)
Minimum operating system requirements: Windows operating system: Windows 11, Windows 10, Windows Server 2022, Windows Server 2019, or Windows Server 2016 macOS: macOS Sonoma, macOS Ventura, and macOS Monterey Linux: Outlook.com works in both Firefox and Chrome on Linux
Let me know how it goes, I'm here to help you further if needed.
-- Diane