02 / SENDING REPUTATION · 7 MIN READ

A Blocklist Result, with Its Limits Attached.

There is no single internet-wide blacklist. This site checks one provider explicitly and never turns a failed lookup into a clean bill of health.

Check the Actual Sending IP

Use the public IP identified in a recipient’s rejection or your outbound mail logs. A browser’s public IP may belong to a home connection, corporate gateway or VPN. A domain’s MX servers normally receive mail; a different platform may send its newsletters or transactional messages.

What SpamCop Represents

The SpamCop Blocking List uses reported-mail evidence and changes over time. It can include legitimate infrastructure affected by unwanted traffic or mistakes. A listing is a data point, not an accusation about an individual.

SpamCop recommends considering its data as part of a wider filtering decision. A result here cannot reveal a receiver’s private reputation system, explain every rejection, or guarantee inbox placement.

Reference: SpamCop — Blocking List overview.

Four States, Not One Green Score

How Access Is Checked

For each IPv4 report, the service queries the reversed IP under bl.spamcop.net, a known-positive control and a known-negative control. It only recognizes the expected listing code. An empty success, unusual address, truncated reply or failed control remains unknown.

All DNS questions travel through Google Public DNS over HTTPS. Resolver caching can affect what is observed. The report includes a timestamp and query details so a snapshot is not mistaken for permanent status.

Reference: SpamCop — DNS lookups from custom software.

Free Checks, Clear Coverage

The automated checks here use public DNS and the SpamCop IPv4 blocklist. No paid data subscriptions are enabled. Domain mode inspects mail DNS; it is not a domain-blocklist scan. We do not query Spamhaus or URIBL automatically, scrape their websites, or present their results as if this site had checked them.

For an additional opinion, open these official lookup pages yourself. These are external links, not automatic checks or submission buttons.

• SpamCop IP Lookup ↗ — sending IPv4 reputation.
• Spamhaus IP & Domain Checker ↗ — look up the IP or domain identified in the rejection.
• URIBL Domain Lookup ↗ — domain reputation; not a test of every outbound mail server.

Access references: SpamCop DNS Usage ↗ · SpamCop Cost Information ↗ · Spamhaus Access Conditions ↗ · URIBL Access Conditions ↗.

If You Need a Listing Reviewed

MXBLACKLIST is lookup-only. We do not accept spam uploads, send complaints, nominate domains or IPs for listing, or submit review or removal requests. The steps below are for you to carry out directly with the responsible provider.

1. Confirm the exact resource and list. Read the bounce, then verify the cited IP or domain on the operator’s official lookup page. A missing SPF record or a DNS timeout is not proof of blocklisting.
2. Identify who controls it. If a shared Microsoft 365, hosting or email-service IP is listed, contact that provider. Act only for a domain or IP you own or are authorized to administer.
3. Resolve the underlying issue. Review authorized sending logs, secure compromised accounts or applications, and correct the issue supported by the evidence. Do not change unrelated mail records to clear a warning.
4. Follow the operator’s review process. Use the guidance below. Submit only if that operator offers a review path for the specific listing; do not send repeated requests.
5. Keep a small, accurate record. Include the affected resource, listing reference, time, your administrative relationship and the relevant remediation. Follow the provider’s evidence requirements; never send passwords, API keys or unrelated customer data.

SpamCop: Investigate, Then Allow Automatic Expiry

Use the official IP lookup to read the listing and its current timing. SpamCop says an IP normally delists after 24 hours without new reports, with additional propagation time possible. It asks administrators not to request early removal simply because they fixed the cause. For a genuine technical or reporting error, use the administrator dispute instructions and explain your authority over the IP. End users should work through their mail provider.

Read SpamCop’s Administrator Review Instructions ↗

Spamhaus: Follow the Specific Listing’s Next Steps

Look up the exact IP or domain in the official checker, read the listed reason, and resolve the cause first. If eligible, follow the review or removal steps shown for that listing. Some IP cases require the network provider to act. Spamhaus states that removal is free; using its form does not guarantee approval.

Open Spamhaus’s Checker ↗ · Read Spamhaus’s Domain Review Guidance ↗

URIBL: Check the Domain, Then Use Its Own Review Process

Verify the domain with URIBL’s lookup. Its official site provides a separate delisting process that requires an account. If you administer the affected domain, follow those instructions and explain the correction or suspected error. MXBLACKLIST does not create the account, forward your evidence or make the request.

Read URIBL’s Lookup and Submission Guidance ↗

If You Want to Report Abuse

Use your mail provider’s reporting feature or the relevant operator’s official help process yourself. Read its evidence and privacy requirements first, and report only genuine abuse supported by the original evidence. A listing result alone is not a reason to report someone. Do not upload or forward spam messages to MXBLACKLIST.