How do I fix authentication failures caused by using the same Gmail account in different Vtiger CRM instances?

This issue occurs because Google restricts simultaneous authentication of the same email address across multiple Vtiger (.com or WS) instances for security reasons. To fix this, you must revoke existing Vtiger connections in your Google Account and re-authenticate.

Follow these steps to restore access and allow the same email ID to be used again:

1. Open your Google Account Settings.
2. Go to Security > Third-party apps with account access.
3. Find and select Vtiger from the list.
4. Revoke access by removing all Vtiger connections.
5. Return to your instance and re-authenticate your Google email account.

After revoking and reconnecting, the email account should authenticate normally, and schedulers will resume working automatically.