Move from explanation to action with the matching DomainCheck.co.uk tools for this topic.
Confirm the domain still resolves and the basic status is what you expect.
Useful when you need to inspect and compare multiple affected domains quickly.
Bring in deeper support when reputation and visibility issues overlap.
A domain that is "not resolving" is usually a DNS or delegation problem, but the cause can sit in several different places. That makes it distinct from a general website downtime issue or a registrar/account problem. This article exists separately because readers need a clean troubleshooting path: check whether the domain is registered, delegated, configured, cached, or blocked. Those steps are different enough that they deserve their own guide.
Confirm the registration is still active before debugging DNS. Expiry creates a different failure path.
If nameservers or records were edited recently, propagation or delegation mismatch is the first thing to rule out.
Check apex and www separately. One missing record is enough to make the site look broken.
That often points to DNSSEC, authoritative nameservers, or connectivity rather than a missing record.
If the domain is active but not resolving, check the delegation path first: registration, nameservers, zone records, then resolver and cache behaviour.
When a domain is not resolving, the problem is usually that the DNS lookup is failing somewhere between the browser and the authoritative DNS records. That does not always mean the website is offline. It often means the domain cannot be translated into an IP address reliably.
The fastest way to narrow it down is to separate the problem into layers. First, confirm the domain is spelled correctly and that you are testing the exact host name you expect. example.co.uk and www.example.co.uk are not always configured the same way. A missing www redirect or a missing apex record can make it look as though the whole domain is broken when only one record is absent.
Next, check whether the domain is still registered and not expired. If the registration lapsed, the nameservers may stop delegating as expected, or the domain may enter a grace or redemption stage depending on the registry. That is a different problem from a bad DNS record, so the fix will be different too.
| Symptom | Likely layer | First check |
|---|---|---|
| NXDOMAIN | Registration or delegation | Confirm the domain exists and that the nameservers are correct. |
| SERVFAIL | DNSSEC or authoritative server issue | Check DNSSEC chain, DS records, and nameserver health. |
| Timeout | Nameserver reachability | Test authoritative DNS directly and look for network or server outages. |
| www works, root does not | Record-level configuration | Compare the apex and www records separately. |
A missing record, a bad delegation, and a local cache issue can look similar at first. If you change multiple things at once, you make the root cause harder to find.
If the domain is still registered, look at the nameservers. A common failure is delegation to the wrong nameservers, stale nameserver data after a migration, or nameservers that are online but not answering correctly. If the nameservers themselves are wrong, no amount of editing records elsewhere will help because the internet is being sent to the wrong place.
If the nameservers are correct, inspect the zone records. The domain may be missing an A record or AAAA record, or a CNAME may point somewhere invalid. It is also possible for the apex domain to work while www fails, or the reverse. If only one hostname is broken, that usually points to a record-level issue rather than a full delegation failure.
Propagation and caching can make diagnosis messy. DNS changes do not appear everywhere at once, and resolvers cache responses for different periods. If a change was made recently, some users may see the old answer while others see the new one. That is normal during a transition, but it should settle if the records are correct. If the issue persists well beyond the expected cache window, look again at the source configuration.
DNSSEC is another possible cause. If DNSSEC is enabled but the signatures, DS records, or chain of trust are inconsistent, some resolvers will fail the lookup even if the records look fine in a basic query. This kind of failure often appears as a SERVFAIL rather than a simple missing-record problem.
Local and network-level issues can also confuse the picture. Browser cache, operating system cache, a corporate DNS filter, or a home router can all make a healthy domain appear broken. Testing from multiple networks or resolvers is a good way to separate a local issue from a real DNS issue.