Domain name troubleshooting is faster when you check registration, nameserver delegation, DNS records, hosting, SSL, and email in the correct order. This checklist helps isolate the failing layer before you make changes.
1. Confirm Registration Status
- Verify the domain is active and has not expired.
- Check that renewal and payment were completed.
- Confirm the registrar account is accessible and protected with multifactor authentication.
- Review recent transfer, contact, or lock changes.
2. Check Authoritative Nameservers
Compare the nameservers listed at the registrar with the nameservers expected by the DNS provider. If they do not match, editing records in the wrong control panel will have no public effect.
3. Test DNS Records
- A and AAAA records for the root domain and required hosts
- CNAME records for aliases such as www
- MX records and their priorities
- TXT records for SPF, DKIM, DMARC, and verification
- CAA records when certificate issuance is restricted
Consider TTL and resolver caching before assuming a recent change failed.
4. Separate DNS from Hosting
If DNS returns the expected IP address, test whether the web server responds. A correct DNS answer does not prove the site files, virtual host, application, firewall, or database are working.
5. Check HTTPS and SSL
Confirm the certificate covers the requested hostname, has not expired, and is installed with the required intermediate certificates. Redirect loops can come from conflicting application, proxy, CDN, or server rules.
6. Diagnose Email Separately
Check MX records, the mail-provider account, mailbox status, and authentication records. Use the exact error from the sending or receiving server. Website availability and email delivery can fail independently.
7. Review Recent Changes
Record when the problem began and list changes to nameservers, DNS, hosting, CDN, SSL, email, firewall, plugins, or account access. Roll back only when you understand the previous working state.
Information to Collect Before Escalation
- Domain and affected hostname
- Exact error message and timestamp
- Networks, devices, or regions affected
- Current nameservers and relevant DNS answers
- Recent changes
- Hosting or mail account reference
Never send passwords, one-time codes, full payment details, or domain-transfer authorization codes in an ordinary support message.
Detailed Troubleshooting SOP
For an operational workflow, use our domain troubleshooting SOP. You can also review the DNS zone file guide and NS and MX records guide.
Frequently Asked Questions
Why does a domain work for some users but not others?
Different resolvers may hold cached answers, or the issue may be regional, network-specific, or related to IPv4 versus IPv6.
Should I change nameservers immediately?
No. First identify the authoritative provider and verify the intended zone. Unplanned nameserver changes can create a wider outage.
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