Apple Mail Quitting after Turning on Mail Extensions

An Apple Mail crash is being reported by Mail Extension manufacturers, which has been isolated to Apple Mail.  Those who use any extension may experience an intermittent or persistent crash when using any Mail extension, preventing them from using Apple Mail. This issue will continue until Apple releases a fix in a later update.

Disabling junk mail filtering in Apple Mail has been shown to be an effective workaround.

Follow the steps below to turn off junk mail filtering.

1. Go to   ==> System Settings ==> Privacy & Security ==> Extensions ==> Added Extensions ==> Toggle Off Daylite
2. Open Mail

3. From the menu bar, choose Mail ==> Settings

   

4. Click the Junk Mail tab

5. Turn off Enable junk mail filtering

   

   
   
6. Quit Mail
7. Reopen Mail
8. From the menu bar, choose Mail ==> Settings
9. Navigate to Extensions
10. Toggle back on the Daylite Extension

We have also received reports that clearing out the Mail.app Preference and Cache files can solve this issue as well. However, we highly recommend reaching out to Apple for assistance doing this. 

We strongly suggest reaching out to Apple about this bug within their Mail app in order for them to resolve the problem. You can reach out to Apple on their feedback page.