| Method | Difficulty | Estimated Time |
|---|---|---|
| Clear Keychain Access | Medium | 5 Minutes |
| Remove License Files | Easy | 3 Minutes |
| Clear App Cache | Medium | 5 Minutes |
What is Microsoft Word Login Error on Mac?
The Microsoft Word login error on Mac typically occurs when the authentication token stored in the macOS Keychain becomes corrupted or mismatched. Users often see messages like “Another account from your organization is already signed in” or “Sign in Required.”
This error prevents users from accessing their Microsoft 365 subscription features. It often happens after a password change, a macOS update, or when switching between multiple Microsoft accounts.
Step-by-Step Solutions
1. Clear Office Credentials from Keychain Access
The most common cause is a conflict in the macOS Keychain. Clearing these entries forces Word to create a fresh, clean login session.
Open **Keychain Access** via Spotlight (Cmd + Space). Search for “Office” in the search bar. Delete all entries related to Microsoft Office, such as `com.microsoft.AdalCache`.
Restart your Mac and try signing into Word again. This usually resolves 90% of authentication loops.
2. Use the Microsoft License Removal Tool
Microsoft provides a dedicated tool to clear license files that might be stuck. This is safer than manual deletion for most users.
Download the “License Removal Tool” from the official Microsoft support site. Run the `.pkg` file and follow the on-screen instructions to scrub existing license data.
Once finished, open Word and sign in with your Microsoft 365 credentials. This resets the activation state without deleting your documents.
3. Clear Word Cache via Terminal
Sometimes, the local cache folders in the Library directory prevent a successful handshake with Microsoft servers. You can clear these using the Terminal.
Close all Office applications. Open Terminal and run the following command to navigate to the Containers folder and remove the Word cache:
rm -rf ~/Library/Containers/com.microsoft.Word
rm -rf ~/Library/Group\ Containers/UBF8T346G9.OfficeBe careful with the `rm -rf` command. Ensure you have backed up your data before running scripts that delete directories.
4. Check for System Updates
An outdated version of macOS or Word can cause compatibility issues with modern authentication protocols.
Go to the **App Store** and check for updates under the “Updates” tab. If you installed Word via the Microsoft installer, open Word, go to the **Help** menu, and select **Check for Updates** to launch Microsoft AutoUpdate.
Ensure you are running the latest version of the Microsoft AutoUpdate (MAU) tool itself for the best results.