Our IP or domain is on a Spamhaus list and mail won't deliver
Spamhaus has several lists: SBL (spam source), CSS (snowshoe), XBL (compromised botnet), DBL (domain), PBL (dynamic IP). First identify which listing you have, fix the root cause, then delist via spamhaus.org/lookup. Premature delisting without a fix causes relisting with cooldown.
Try this first
- 1Run a lookup on spamhaus.org/lookup with your IP and domain. Note which list, with which reason and evidence.
- 2PBL (Policy Block List) usually means you're sending from an end-user IP. Fix: relay via an SMTP smarthost (M365, Google, ESP), don't run your own.
- 3SBL or CSS likely means your IP sent spam. Find the source: compromised account, vulnerable web form, malware on a workstation. Fix that first.
- 4DBL targets your domain. Often look-alikes, compromised WordPress, or phishing pages on a subdomain. Clean up and gather evidence for delist.
- 5Submit delist via the Spamhaus Removal Center. Describe the concrete fix you made. No vague promises.
When to bring us in
On CSS or SBL with no idea about the source, you need a logging audit of your MTA and outbound traffic before delisting.
See also
- Our emails land in spam for some recipientsAlmost always an SPF, DKIM, or DMARC setting that is wrong or missing, or a sender name that mimics a well-known brand.
- Someone reports receiving phishing emails "from us"Read: spoofing. Someone is abusing your sender name, not necessarily your actual mailbox.
- An email bounces (NDR): delivery failedThe NDR text usually states the exact reason. Reading it is step one.
None of the above fits?
Describe your situation below. We pass your input plus the steps you already saw to our AI and return tailored next-step advice. If it's too risky to DIY, we'll say so.
Or skip the DIY entirely
Our Managed IT clients do not look these things up. One point of contact, a fixed monthly price, resolved within working hours.