Log in to WHM panel and click on the "Edit MX Entry" link from the "DNS Functions" menu.
Code:
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| DNS Functions |
|_____________________________________|
| * Add a DNS Zone |
| * Add an A Entry for your Hostname|
| * Delete a DNS Zone |
| * Edit DNS Zone |
| * Edit MX Entry |
| * Edit Zone Templates |
| ... |
|_____________________________________|
On this page you will see a table with title:
Code:
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|Choose a Domain to Edit|
|_______________________|
Click on the required domain in the list and click on the "Edit" button on bottom of page. Enter the "Priority" and "MX Destination" and click on the "Save" button.