I've been working with a small start-up that relies on a mail server to send critical password reset codes and one-time passwords for new accounts. After more than a year of sending emails without issues, we recently discovered that our mail server's IP address has been added to a blocklist. I'm not exactly sure how this occurred or what steps I need to take to get off the list. I did some digging and found that while my domain isn't listed, the IP is flagged with the reason being suspect behavior, misconfiguration, or a poor sending reputation. Can anyone share their experience or knowledge on how to resolve this?
5 Answers
Visit check.spamhaus.org and search your domain. If it's listed, you can request delisting there. If your domain isn’t showing as listed, then the issue might be elsewhere. Also, double-check that your DNS SPF record is properly set up to avoid future problems.
Not knowing how you ended up on the list is a bad place to start for getting delisted. It’s vital to identify the underlying cause; otherwise, you might face this issue again.
You should start by checking out the Spamhaus site at check.spamhaus.org. Just enter your domain there, and it will guide you through some options for getting delisted. It's also a good idea to investigate why your IP got flagged—problems like insecure protocols or DNS issues could be the culprits.
I checked the IP directly, and it doesn’t show any listings. However, it does indicate suspect behavior causing a CSS listing. Seems like I need to dig deeper!
Reverse DNS mismatch is a common issue that could cause this. Make sure your DNS records are correctly set up—that should help clear things up.
Ensure you have both DMARC and SPF correctly configured. Also, check that you’re not running an open relay that anyone can exploit, and ensure you're sending emails only from your owned domain.
Thanks for the tips! I’ve checked everything again, and we have valid SPF, DMARC in place, and we’re only sending from our own domain.
Thanks for the insightful comment!