In order to add 123-reg MX records for your domain name so that 123-reg email works, please do the following:
Firstly, you need to ensure your domain is pointed to our nameservers:
- ns.123-reg.co.uk
- ns2.123-reg.co.uk
If the domain is not pointed to the 123-reg nameservers, you will be unable to manage them from the 123-reg control panel.
For more information on changing your nameservers please view the following article:
How do I change the nameservers for my domain name?
Please Note: It will take between 24 - 48 hours for the new MX records to become active.
2
In the Domain names section, select the relevant domain name in the drop-down list and click on the Manage button.
3
Scroll down to the Advanced Domain Settings section and click on the Manage DNS (A, MX, CNAME, TXT) link.

4
From the Basic DNS tab.
5
Click on the Change button in the EMAIL SETTINGS (MX RECORDS) section.
6
Select 123-reg email from the Your email is pointing to: drop down list.
7
Click on the Point to service button.
8
Click on the Confirm button to complete the change.