Colinz, you have a couple things going on. This:
They have blacklisted our mailservers IP address.
That's because someone was spamming from the machine where your machine is hosted. There is not a lot you can do about that if the mail is sent from an IP address which is blacklisted. That is a good reason to have your mail sent by and SMTP server.
I have tried all the smtp variants
And what happened when you tried them? Let's focus on one. You need to have one configured correctly so the test email arrives, then you can focus on your Gravity Forms notifications.
New user notifications come from WordPress, usually with the email address email@example.com - that normally looks OK to the mail server when it's hosted on the same machine. It knows that users from that domain are authorized to use the server. It becomes a problem when the email appears to be sent from the person who submitted the form, which is likely NOT on your domain (could be chrishajer @ gmail . com maybe) - that looks like spam or unauthorized to a lot of webhost mail servers, and it's dropped.
The answer, in 99.9% of the cases, is to use an external SMTP server to get more reliable email delivery. The server you authenticate to knows who you are, since you just authenticated, and lets you send email without many restrictions. That's why the external SMTP server normally works. When trying to send email from your web host, there is no authentication, and it looks to the MTA on the host like spam, when it starts seeing mail coming FROM firstname.lastname@example.org and TO email@example.com when your domain is def.com.
Posted 8 years ago on Monday October 8, 2012 | Permalink