Overview:

If employees or students encounter an expired authentication error when trying to log in to Blackboard, access will be blocked. Attempting to sign in again by selecting "Return to Login Page" will not resolve the issue, as the error will persist. 

To fix this, the best approach is to clear your browser’s cache and cookies. Detailed instructions are available for Google Chrome, Firefox, Safari, Microsoft Edge, and Internet Explorer. Once you have cleared your browsing data, make sure to close and reopen your browser before logging in again. 

To prevent future sign-on errors, always log out completely by clicking both the "logout" and "End SSO Session" buttons.

For additional guidance on resolving this problem, please refer to the documentation linked below.