Persistent 'credential propagation unsuccessful' error when mounting Google Drive

[ericstrom100]

Message: "I am consistently encountering an issue when trying to mount Google Drive in Colab. The drive.mount('/content/drive') command fails with the error MessageError: Error: credential propagation was unsuccessful.

Additionally, attempts to diagnose the issue by running print(output.eval_js('google.colab.kernel.google.user.getEmail()')) also fail, showing MessageError: TypeError: Cannot read properties of undefined (reading 'user').

Currently using the Brave Browser.

I have already performed the following troubleshooting steps:

Reran the drive.mount() cell multiple times.
Turned off popup blockers for research.colab.google.com.
Cleared my browser's cache and cookies.
Switched between Brave Browser and Firefox.
Started entirely new notebooks.
Attempted to revoke Colab's access to Google Drive via my Google Account Security settings (myaccount.google.com/security -> Third-party apps with account access). However, 'Google Colaboratory' was not listed as an app with access.
Confirmed that I cannot see my Google profile picture or initial in the Colab top right corner.
Checked 'Runtime -> Manage sessions' and could only see session names, no account information.
Performed a complete browser-level sign-out from all Google accounts, cleared cache/cookies, restarted the browser, and signed back in before trying Colab again.

Despite these extensive steps, the issue persists. It seems that Colab is unable to establish or find my Google account's credentials within the session, preventing Drive from mounting."