Hi @JUN
Do you mean you can't log account in to Office apps?
What is your account type, such as a personal Microsoft account, or an organization-assigned Microsoft 365 account?
I suggest you close all Microsoft applications (Such as Office, Teams, OneDrive etc).
- Download the OLicenseCleanup.zip file, extract the OLicenseCleanup.vbs script, and run it using elevated permissions. This action is used to remove previous licenses and cached account information. For more, please refer to 'Method: Use scripts to automate the cleanup process'.
- Relaunch Word and sign in your account for a check.
If the step does not work, please try followings.
- Search %AppData% in Windows Search box, and navigate to Microsoft folder (C:\Users<yourusername>\AppData\Local\Microsoft)
- Cut the OneAuth and IdentityCache folders out of the Microsoft folder and paste them onto your desktop.
- Relaunch Word and sign in. If the issue persists, close Word, copy the OneAuth and IdentityCache folders back into the Microsoft folder, when it asks if you want to overwrite, say NO.
- Relaunch Word and sign in again.
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