How to do it...

Go through the following steps to disable outgoing notifications in Jira:

1. Navigate to Administration > System > Outgoing Mail.
2. Click on the Disable Outgoing Mail button.

Once you have disabled outgoing mail, Jira will no longer send out notifications. If you want to re-enable outgoing mail, simply click on the Enable Outgoing Mail button, and Jira will start sending out emails again.