Authentication Library errors are related to outdated video drivers or environment variables which are not properly configured.

More information about updating video drivers can be found at

To check your environment settings, please follow the steps below:

1. Right-click on My Computer and select Properties.
2. Click on the Advanced tab.
3. Click on the Environment Variables button near the bottom of the window.
4. Scroll through the variables looking for anything that references your Steam installation directory.
5. If you find a reference to Steam, select the variable where it is present and press the Delete button.
6. Click the OK button twice to exit.
7. Restart your computer.