I would recommend contacting our support team. We work diligently to keep our IP ranges off of blacklists and they should be able to assist you with resolving this by identifying the IP in that range that is responsible and taking action.

I would recommend to use a service like mandrillapp or mailgun to take care of your emails, that would be a quicker and better solution.

In attempting to set up a mail server, and finally getting it working mostly. I discovered this same problem. My test email was received on some external email addresses, but Yahoo put a nice “X-YahooFilteredBulk” header tag into the received email and threw it into the spam folder.

This led me to http://www.uceprotect.net/en/rblcheck.php, which led to http://www.whitelisted.org/. Our IP is not involved in any of the reported incidents, and so I suppose if we had $21/month (or $100+ per 2 years) to spare, we could get whitelisted, and the problem would likely go away, but I do not know.

I’ll be contacting support shortly, as a result of RyanPQ’s suggestion.

Just as an update I see that my droplet IP is, as of now (August 2019), part of a new UCEPROTECT3 blacklist that covers a large piece of DO IP space.

It’s nothing that I’ve done wrong and nothing that anyone in the IP space close to me is guilty of, but the UCEPROTECT website claims that there are a lot of DO droplets sending spam at the moment.

I’ve put a support ticket in to ask what DO are able to do about this - I’d encourage others inconvenienced to do the same.

Just got the notification from monitoring service that it’s removed from the blacklist.

I am getting blacklisted from this entity too. Most of our emails don’t reach do to this.