Many issues involving Google Drive can be fixed by logging out, and then logging back in. Follow the steps below before troubleshooting further.

1.  Right-click on the small Google Drive icon in your System Tray:

2.  Click 'Quit' when the pop-up box appears:

3.  Click on the Start Menu, then type 'Google Drive' and click on the 'Google Drive' app icon to re-launch the software:

4.  You may need to SIGN-IN using your Google account credentials.

5.  Confirm that the Google Drive app icon is showing in your System Tray:

6.  Open your Google Drive folder and confirm you have access to your Shared folders.