Yet another DNS fail at 123reg.co.uk
It's technical but Email from private domains at 123reg have been marked as spam senders by SPF fails at Google's Gmail for months now.
The DNS txt lines at 123reg.co.uk are so long and chaotic that they cannot be sent in a single UDP packet. Google declines to get the full TXT/SPF records and thus marks 123reg.co.uk customer domains as spam senders.
$ dig 123reg.co.uk TXT
123reg.co.uk. 3600 IN TXT "v=spf1 include:a.123-reg.co.uk ip4:188.8.131.52/24 ip4:184.108.40.206 ip4:220.127.116.11/27 ip4:18.104.22.168/24 include:trustpilotservice.com include:spf.mandrillapp.com include:spf.protection.outlook.com include:sendgrid.net include:mailcontrol.com include:s" "pf.em.secureserver.net ~all"
notice the broken bit in quotes near the end >>> include:s" "pf.em.secureserver.net ~all" <<< that's the failure point. Customers with own email sending domains have to guess (from a wide selection) which of the outbound 123reg.co.uk email server will be in use. As you know a domain that sends emails out via another has to inherit that domains SPF record.
Yes they have been told/shown/proven this problem and admitted the issue but have failed to correct the problem. Other proper hosting providers do this technical point correctly. Despite promoting hosted domains as suitable for email and web friendly they disappointingly fail to deliver ( or send correctly ).