Mozilla has learned that a fraudulent SSL certificate for websites belonging to Google has been issued by DigiNotar. This is not a Thunderbird-specific issue and the certificate has now been canceled which should protect most people.
You can manually delete this certificate from any version of Thunderbird with these steps:
- In the Menu bar at the top of the screen, click and then select or , depending on your macOS version.Click the menu button and select .
- Click on the panel
- Select the tab
- Click
- In the Certificate Manager window, select the tab
- Scroll down to DigiNotar and select the DigiNotar Root CA
- Click
- Click
- Because the certificate is "built-in" it will be distrusted but not deleted. Distrusting the certificate has the same effect as deleting it.
to confirm the deletion