How to Fix "Sign in Required: Cached Credentials Expired" in Office on Mac
Make sure your Office apps were closed (inc OneDrive). Open Keychain Access. Look for Microsoft Office Credentials, in the "login" keychain. Delete them. Note: Make a note of your user name and password first. Open the apps again you should see something like this: "To sync changes with OneDrive, Microsoft Excel needs access to your OneDrive folder" Or you might be asked to sign in again. Sign in if required. Re-launch the required apps.
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