A Microsoft file hosting and synchronization service.
Dear @Ava Bell,
Since your personal account works correctly and your business accounts function normally on another device, the issue appears to be isolated to the Web Account Manager (WAM) or the Microsoft 365 identity cache on this specific computer. When the sign-in window becomes unresponsive before displaying the password prompt, it can indicate that Windows is unable to load the modern authentication broker correctly.
As you have already reset OneDrive and cleared its cache, kindly try these steps:
1> Disconnect and reconnect your work or school accounts
In Start Menu, open Settings > Accounts > Access work or school > choose each affected business account > Disconnect
Restart the computer.
Return to Settings > Accounts > Access work or school.
Select Connect, and then sign in again using your business account.
After reconnecting the account, please test the original sign-in scenario.
Please be assured that disconnecting an account from this page will not delete data stored in Microsoft 365 or OneDrive. However, it will remove the account’s connection from this device, and you may need to sign in again to Microsoft 365 applications.
2> Rebuild the Microsoft identity broker cache
Close all Microsoft 365 applications, including OneDrive, Teams, Outlook, and any Office applications.
Press Windows key + R > run: %localappdata%\Packages
Locate the following folder: Microsoft.AAD.BrokerPlugin_cw5n1h2txyewy
Cut the folder and paste it onto your Desktop as a backup. Please do not permanently delete it at this stage.
Restart the computer, and then try signing in again. Windows should create a new broker cache automatically. Access work or school troubleshooter for restoring access to M365 desktop applications | Microsoft Support
I hope the information shared helps point you in the right direction. Please try the steps above and let me know if they work. If not, we can continue working together to narrow this down.
The first response may not always resolve the issue right away, but with your help and more details, we can work toward a solution.
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