I know this is very frustrating but lets pause a moment and see the possible reasons this could be happening.
- 1. Mail Server (SMTP) is Offline
This is a common issue to WHM/cPanel and Plesk servers. Simply restarting the service from the control panel often fixes the issue.
How To Restart Services In WHM cPanel
As an administrator with cpanel credentials you can restart services in the cpanel.
- Login into cPanel with your root/administrator account.
- Search for “Restart” using the search tool on the side panel
- The Services that can be restarted through cPanel are listed down.
- Click on the service that you want to restart. For this example, we shall restart the SMTP service. A popup message prompting for an action will appear, when you click on the service. Click “Yes” to proceed.
- Service will be restarted.
- A success message will appear if the service is restarted successfully.