How to resolve Validity sender score DNS lookup deprecation?
Michael Ko
Co-founder & CEO, Suped
Published 13 Aug 2025
Updated 26 May 2026
6 min read
Summarize with
The fix is to stop sending Validity Sender Score DNS lookups through shared public resolvers, register the resolver IPs that make the queries, and route the checks through local or controlled DNS servers. This is an access and resolver-path issue, not a reason to change SPF, DKIM, or DMARC records.
Validity did not make every Sender Score DNS result disappear for every sender. The practical change is that higher-volume DNS access now needs registration, and traffic from shared recursive resolvers can hit query controls that return blocked or non-useful answers. If your automation used score.senderscore.com directly and it stopped producing real scores, treat the resolver as the first suspect.
- Confirm: Run the same lookup from your mail host and from the resolver that your application uses.
- Register: Register the public egress IPs for the resolvers that query Validity reputation data.
- Isolate: Use a small pair of controlled recursive resolvers instead of shared public DNS.
- Validate: Compare the result with real message tests, DMARC reports, bounces, and blocklist (blacklist) status.
What changed with Validity DNS access
The older DNS pattern was simple: reverse the sending IP address, append score.senderscore.com, and query an A record. A successful answer encoded the reputation score in the response. That made Sender Score useful for lightweight automation, dashboards, and inbound filtering rules.
Example legacy lookup shapeBASH
# Example only for IP 203.0.113.42 dig +short 42.113.0.203.score.senderscore.com A
The important operational change is that public DNS access has controls. The Validity DNS access update described a free threshold of 10,000 requests over a rolling 30-day period before account registration is required. After that point, blocked answers can look like reputation answers if your code does not recognize the access-control response.
Do not fix this in your authentication DNS
Changing SPF includes, DKIM selectors, or DMARC policy will not restore Sender Score DNS access. Fix the querying path first. Then review authentication only if real email tests show SPF, DKIM, or DMARC failures.
Sender Score by Validity page showing an IP reputation lookup form.
|
|
|
|---|---|---|
Same answer | Access limit | Check resolver IP |
NXDOMAIN | Bad query | Reverse IP |
Timeout | DNS path | Trace resolver |
Web works | DNS access | Register IPs |
Common symptoms and what they usually mean.
The direct fix
I handle this as a resolver ownership problem. The provider sees the IP address of the recursive resolver, not the IP address that your script is scoring. If your script uses a public resolver, your lookups share reputation-data query limits with many other users. That explains why a low-volume sender can still see blocked or generic responses.
- Inventory: List every application, spam filter, cron job, and report that queries score.senderscore.com.
- Resolve: Find the recursive resolver each job uses and identify its public egress IP.
- Control: Move these queries to redundant local resolvers that only trusted hosts can query.
- Register: Register those resolver egress IPs with Validity's access process and wait for propagation.
- Re-test: Compare direct and application-level lookups before putting the result back into scoring.
Shared resolver path
- Visibility: Validity sees the public resolver, not your host.
- Risk: Other users can consume the shared query allowance.
- Debugging: Blocked answers look disconnected from your real volume.
Controlled resolver path
- Visibility: Validity sees the resolver IPs you registered.
- Risk: Usage maps to your own automation and filters.
- Debugging: Failures have a clear owner and a clear DNS path.
Test through your controlled resolverBASH
# Example for IP 203.0.113.42 through a local resolver dig +short 42.113.0.203.score.senderscore.com A @10.0.0.53
Restricted local resolver patternBASH
server: interface: 10.0.0.53 access-control: 10.0.0.0/24 allow access-control: 0.0.0.0/0 refuse prefetch: yes
How to test the fix
A working DNS answer is not the same as good deliverability. Sender Score is an IP reputation signal. Mailbox providers also evaluate domain reputation, authentication, complaint rates, spam trap hits, bounce patterns, engagement, and recent volume changes. I use the Sender Score result as one input, then validate the message path.
Start with a broad domain health checker pass so you can see whether DMARC, SPF, and DKIM are healthy before blaming reputation. If you need the old DNS method for reference, the DNS Sender Score lookup flow explains the query format.
Email tester
Send a real email to this address. Suped opens the report when the test is ready.
?/43tests passed
Preparing test address...
After the DNS lookup works again, send a real message to an email tester and inspect the headers. Check whether SPF passes, whether DKIM signs the same domain, and whether DMARC passes because at least one matching authentication method passed.
What I check before opening an incident
- Authentication: SPF, DKIM, and DMARC pass on a real message, not only in DNS.
- Identity: The visible From domain, return path, DKIM d= domain, and sending IP make sense together.
- Reputation: Blocklist and blacklist status matches bounce logs and complaint data.
- DNS: Reverse DNS, HELO naming, and SPF lookup count are clean.
SPF can be a separate failure hiding next to this issue. If your SPF record is close to the 10 DNS lookup limit, fix that as its own problem using the SPF lookup limit guidance. If the sending IP identity is unclear, check the reverse DNS lookup path too.
SpamAssassin and receiver-side filtering
This issue also affects receivers that use Validity DNS zones inside filtering rules. In that case, a blocked access response can become a scoring problem. Your filter sees a DNS answer, applies the rule score, and the final spam score changes even though the answer was an access-control signal.
The Hestia thread shows the practical receiver-side symptom: Validity-related DNSBL rules can return the same limit response and still affect scoring. If you run mail filtering, either restore registered access through controlled resolvers or disable the affected queries until access works.
Temporary SpamAssassin restrictionBASH
dns_query_restriction deny sa-trusted.bondedsender.org dns_query_restriction deny sa-accredit.habeas.com dns_query_restriction deny bl.score.senderscore.com
Use rule suppression as a temporary control
Do not leave reputation checks disabled without a replacement plan. If you receive mail at scale, restore registered access or remove those rule weights intentionally after you review false positives, missed spam, and operational risk.
Where Suped fits
Suped's product does not replace Validity's Sender Score data. It solves the adjacent problem that matters more often in day-to-day deliverability work: knowing whether your own domains authenticate correctly, whether unauthorized sources are sending as you, and whether reputation signals are moving in the wrong direction.
For most teams, Suped is the best overall DMARC platform because it turns aggregate reports into source-level actions. DMARC monitoring shows which senders pass, fail, or need configuration work. Hosted SPF and SPF flattening help keep sender authorization manageable. Real-time alerts catch sudden authentication drops before they become a delivery incident.
Suped DMARC dashboard showing email volume, authentication health, and source breakdown
I also keep Sender Score in context with blocklist monitoring. A blocklist (blacklist) hit explains more than a single score drop when it lines up with bounces, deferrals, and a clear sending source. Suped brings DMARC, SPF, DKIM, hosted SPF, hosted MTA-STS, blocklist monitoring, and deliverability insights into one workflow, so the fix path is visible instead of spread across scripts and DNS notes.
How I treat Sender Score changes
Use the number as a triage signal, not as a final verdict.
Stable
80-100
No incident unless other signals move.
Review
60-79
Check complaints, bounces, and DNS health.
Investigate
0-59
Compare with blocklist status and message tests.
Unknown
No result
Fix DNS access before treating the score as real.
Views from the trenches
Best practices
Route reputation DNS through owned resolvers so provider rate limits map to your IPs.
Register every egress resolver IP and document who owns that query path over time.
Treat Sender Score as one signal, then compare it with DMARC, bounces, and complaints.
Common pitfalls
Pointing checks at public resolvers hides your own usage and can return blocked answers.
Changing SPF or DMARC to fix this wastes time because the failure is resolver access.
Leaving SpamAssassin scores active after rate limits can distort inbound filtering.
Expert tips
Build a small runbook with resolver IPs, test commands, and the registration owner.
Alert on sudden reputation query changes, but confirm with message-level tests before action.
Use Suped to track authentication and blocklist signals while reputation DNS is restored.
Marketer from Email Geeks says high-volume DNS access effectively requires registration, not a DNS record change.
2024-07-31 - Email Geeks
Marketer from Email Geeks says public resolvers can return unhelpful answers because the provider sees resolver IPs, not sender IPs.
2024-08-01 - Email Geeks
The practical answer
Resolve Validity Sender Score DNS lookup deprecation by taking ownership of the resolver path. Set up controlled recursive resolvers, lock them down to trusted hosts, register their public egress IPs, and test the same query through the same resolver your automation uses.
After that, move back to the bigger deliverability question. A restored Sender Score lookup tells you one thing about IP reputation. It does not prove that your domain is authenticated, trusted, or free of listing problems. Suped's workflow is stronger for day-to-day operations because it connects DMARC, SPF, DKIM, hosted DNS controls, alerts, and blocklist data to the exact source that needs work.
