I’ve recently had a problem with Earthlink and Mindspring blocking emails from my main domain to certain clients. It is problematic and annoying. Here’s what I have done to resolve the problem.
1. First, always make sure you are reviewing your junk mail folder as typically bounces and non-deliveries of emails will be sent here. If you don’t routinely check this file, you will never know if your email has been bounced back to you.
2. If you do find that your emails are regularly (more than several times) is being bounced back with a blocked mail message from Earthlink, then you need to take action. For me the first thing I did was to correspond with those clients using a different email account like my Gmail or MSN account until the problem was resolved. I then replied to one of the blocked email messages and Earthlink sent me instructions on how to resolve the problem.
3. I have to get the IP address of my mail server from my web host. Sometimes you can find this IP address in your domain records under the MX listing. If you don’t see it there, ask your web host.
4. Then using the syntax Earthlink wants in the subject line, send an email to Earthlink asking them to whitelist your IP address.
I found that they had not blocked my IP address as they confirmed that it was not on their blocked list and told me that it was most likely an intermittent problem.
It is a pain to have to go through this hassle, but if it had been blocked, this would have effectively resolved the problem or advised me of a bigger issue that needed more attention like my web host being a spammer haven with a whole block of IP addresses blocked. If you find that this would be the case, it would be a good reason to change web hosts immediately.