cPanel's "Email deliverability" menu item reports this problem for my domain.
The system uses an alternate HELO of “s1.n2.n3.n4.static.myhostcenter.net” when sending mail from the “example.com” domain.
The system sends the domain “s1.n2.n3.n4.static.myhostcenter.net” in the SMTP handshake for this domain’s email. “s1.n2.n2.n4.static.myhostcenter.net” does not resolve to any IP addresses.
To fix this problem, contact your system administrator and request that they create a DNS “A” record for “s1.n2.n3.n4.static.myhostcenter.net” whose value is “1.2.3.4”.
However, when I try to add the suggested DNS "A" record using cPanel's "Zone manager", the cPanel interface automatically appends example.com to the end of the name. This is true whether or not I put a "." at the end of the name.
The system uses an alternate HELO of “s1.n2.n3.n4.static.myhostcenter.net” when sending mail from the “example.com” domain.
The system sends the domain “s1.n2.n3.n4.static.myhostcenter.net” in the SMTP handshake for this domain’s email. “s1.n2.n2.n4.static.myhostcenter.net” does not resolve to any IP addresses.
To fix this problem, contact your system administrator and request that they create a DNS “A” record for “s1.n2.n3.n4.static.myhostcenter.net” whose value is “1.2.3.4”.
However, when I try to add the suggested DNS "A" record using cPanel's "Zone manager", the cPanel interface automatically appends example.com to the end of the name. This is true whether or not I put a "." at the end of the name.