If you have deleted or need to add the backup MX record, then please make sure you enter your DNS MX record using the format below.
Record Type: MX (Mail Exchange Record)
Record Data: mlmx.secure-svr.com
Record Preference: 50
To add the MX record, please select your hosting space, then click Domains. Select the desired domain from the domains list. Click the Edit DNS Zone records. Click the Add record button. Change the type to MX Record and enter the information below.