From the UD Bugzilla homepage, click on the Preferences link.
The User Preferences page will be presented with the first tab open: General Preferences.
Click on the second tab titled Email Preferences.
As a shortcut, you can click the button for Enable All Mail or Disable All Mail.
To customize the email setting, read through the page options and make sure your preferences are checked.
When you a satisfied with your chosen settings, click the Submit Changes button.