Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hi, Juha Vainionpää
Since the web apps still work, the subscription itself is usually fine, and the problem is more likely with the Windows sign-in layer on that PC rather than the Microsoft account itself.
Here are some suggestions you can try:
First, run the built-in Microsoft 365 sign-in troubleshooter. Open Get Help, type “sign in to Microsoft Office,” and follow the prompts. It is recommended that you start there because it's listed specifically for Microsoft 365 sign-in problems.
If that does not help, go to Windows Settings > Accounts > Email & accounts and remove any old Microsoft accounts under “Accounts used by other apps,” then add your personal Microsoft account again. It is also suggested that you temporarily turn off the Windows Hello-only sign-in option and try signing in with your password instead of your PIN.
One more good check is Internet Options. Press Win+R, type inetcpl.cpl, then restore/reset Internet settings, make sure TLS is enabled, proxy is off, and if needed reset the network stack. It is recommended that you try this because desktop Office sign-in can fail when those Windows internet settings are stuck, even if the browser still works.
Thank you for your patience in reading, I hope this information has been helpful to you.
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