Warming up
A domain blocklisting can take a sending domain from healthy to unusable overnight. Warmerly checks yours daily against Spamhaus DBL, SURBL and URIBL — from its own resolver, because these zones refuse queries that arrive via public DNS.
These three are the domain-reputation lists that filtering systems actually consult when deciding what to do with a message that mentions your domain. Warmerly queries each one by plain DNS lookup for every sending domain in your workspace, records the verdict, and links straight to the right delisting form when something appears.
Every one of these zones signals 'your query was refused' using an address inside the same 127.x range it uses for real listings. Spamhaus answers 127.255.255.x; SURBL and URIBL answer 127.0.0.1. Any checker that treats a 127.x answer as a hit will report every customer as blacklisted the moment it gets rate-limited. Warmerly classifies each zone's codes explicitly and treats anything it does not recognise as an error — never as a listing.
Spamhaus, SURBL and URIBL all refuse queries arriving from Cloudflare, Google and Quad9 resolvers. A monitoring feature built on the default system resolver therefore returns refusals for every domain it checks, forever, and either reports nothing or reports nonsense. Warmerly runs its checks through a dedicated resolver so the answers are real.
A domain blocklisting is one of the few deliverability problems that is genuinely binary. One day your mail lands; the next day a large share of receivers reject or junk it outright because your domain appears on a list they consult. The listing rarely announces itself. What you notice, usually a week later, is that the replies stopped.
IP blocklists such as Spamhaus SBL list sending addresses. If you send through Google Workspace, Microsoft 365 or any shared provider, the IP is not yours and a listing there is not yours to fix — the provider handles it, and it is largely out of your control.
Domain blocklists list the domains that appear in the message: the sending domain, the domains of links in the body, and the domains a reply would go to. Those are yours. Spamhaus DBL, SURBL and URIBL are the three that matter, and a listing on any of them follows your domain across every provider you send through. Changing ESP does not help. That is why Warmerly monitors domain reputation rather than reporting an IP you do not own.
The first cause is by far the most common among cold senders, and it is entirely preventable. Spam traps are why verification before import is not optional, and why Warmerly ships verification in the same product rather than selling it separately.
Spam-trap hits are the leading route onto a domain blocklist for cold senders, and a trap address is indistinguishable from a real one by eye. Running a list through verification first costs minutes; delisting costs weeks.
The domain's mailboxes show the listing on their own pages with the zone name, what that zone's code actually means — spam domain, phishing, malware, abused legitimate domain — and a direct link to the delisting form for that specific list. The health score reflects it, which means the affected mailboxes' sending allowance narrows rather than continuing at full volume into receivers that are already rejecting them.
Warmerly does not attempt to submit delisting requests on your behalf. Every one of these lists requires the domain owner to attest to what was fixed, and an automated submission from a third party is both against their terms and a good way to get a request denied and a domain re-listed faster.
When a check cannot get a reliable answer — a refused query, a timeout, an unrecognised response code — Warmerly says the status is unknown and will try again on the next run. It does not round that to 'clear', because a monitor that reports clear when it did not actually check is worse than no monitor at all: it converts an unknown into a false assurance.
It also does not round it to 'listed'. Telling a customer their domain is blacklisted when in truth the resolver was rate-limited is the failure mode that makes people distrust the whole product, and it is the single most common bug in home-grown blocklist checks.
The three domain-reputation zones that matter for sending domains: Spamhaus DBL, SURBL and URIBL. These list domains rather than IP addresses, which is the reputation you own and can fix.
If you send through Google Workspace, Microsoft 365 or any shared host, the sending IP is not yours and a listing on it is not yours to resolve. Reporting it would produce alarm you cannot act on.
Checks run daily per sending domain, and the result appears on the affected mailboxes with the zone, the meaning of the code, and a delisting link.
No, and no reputable tool can. Every list requires the domain owner to submit the request and attest to what was fixed. Warmerly identifies the listing, explains what the code means, and links you straight to the right form.
No. It means the last check could not get a reliable answer, usually a refused or rate-limited query, and it will be retried. It is deliberately not reported as clear, because an unchecked domain is not a clean domain.
Run a free check on any domain — authentication and reputation — and see what receivers see before your next campaign goes out.