A WHMCS installation will send notification emails to admin users for relevant system events, self-diagnosis of errors or misconfigurations, and other important notifications. 

For example, this includes:

• Daily Cron Job Activity Report.
• Domain Synchronisation Cron Report.
• Daily System Cron Attention Needed.
• Pop Cron Did Not Run.
• License Limit Near, Reached or Exceeded.

The frequency of these emails varies depending on the context and perceived impact of the problem.

To stop receiving System Emails, perform these steps:

1. Go to Configuration > System Settings > Administrator Roles.

2. Click Edit for the desired role.

3. Uncheck System Emails in the Email Messages section.

4. Click Save Changes.

For more information, see Managing Administrator Roles.