Dear Kathy Anderson
Welcome and thank you for sharing your problem in our Q&A forum!
I understand that being constantly prompted to log in every time you access Excel on your Mac is frustrating.
According to my research, macOS stores Office passwords in the Keychain Access application. If this stored information is corrupted or outdated, Office will constantly prompt you to re-authenticate. Outdated application files can also be a factor.
Please try the following troubleshooting steps:
1.Delete the stored login information in Keychain Access: This forces Office to retrieve a new, uncorrupted login code.
A. Close all Office applications (Excel, Word, Outlook, etc.).
B. Open Keychain Access:
- Go to Applications >> Utilities >> Keychain Access.
C. Search and Delete Items: Use the search bar in Keychain Access to search for:
D. Delete any items related to Office login information, specifically those named:
- Microsoft Office Identity Settings
- Microsoft Office Identity Cache
E. Relaunch Excel and sign in once.
2.If clearing the Keychain is not sufficient, you can use the Terminal to manually reset the authentication state for Office apps.
- Open Terminal and run this command:
defaults write com.microsoft.Word ResetOneAuthCreds -bool YES
- You can replace "Word" with any other name, such as Excel, PowerPoint...
3.Ensure "Keep Sign-in" is selected When you sign in again after deleting the Keychain, be sure to save your login information.
- Open any Office application (e.g., Excel).
- When prompted to sign in, enter your Microsoft Business account email and password.
- Note: The sign-in process for Microsoft 365 apps uses a web-based authentication window. When the prompt "Stay signed in?" appears during this web-based flow, be sure to select Yes.
- Wait for the authentication process to complete.
4.Check for Updates: Make sure your application is running the latest version, as this often contains important patches for login errors.
- In Excel, go to the Help menu > Check for Updates to ensure Office is the latest version.
5.Verify Your License Confirm that you are logging in with a valid and active business account with a valid license.
Please try these steps and let me know the results. Please share any details or error messages if the problem persists, I'm happy to help!
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