DNS Server Not Responding – Common Causes
A “DNS server not responding” error means your device cannot get an answer from a DNS server when trying to access a website or online service. This does not always mean the website itself is down—it usually indicates a problem somewhere in the DNS lookup process.
This type of error can be frustrating because it often appears suddenly and may only affect some users, locations, or networks.
Common Causes of a DNS Server Not Responding Error
Incorrect Nameserver Settings
If a domain’s nameservers are set incorrectly, missing, or pointing to servers that no longer exist, DNS queries will fail. This commonly happens after:
- Changing hosting providers
- Switching DNS providers
- Editing nameservers without completing the setup
When nameservers are wrong, no DNS records can be found for the domain.
Expired or Misconfigured DNS Records
DNS records may be:
- Missing
- Incorrectly formatted
- Pointing to outdated servers
This includes A records, MX records, and TXT records. Expired records or incomplete configurations can prevent DNS servers from responding correctly to requests.
ISP or Local DNS Cache Problems
Sometimes the issue is not the domain itself but the DNS resolver being used by the visitor.
Common scenarios include:
- Internet Service Provider (ISP) DNS servers caching outdated records
- Local device DNS cache holding old information
- Router-level DNS issues
This is why a website may work for some users but not for others.
Firewall or Security Rule Conflicts
Security systems can sometimes block DNS traffic unintentionally. This may include:
- Firewalls blocking DNS ports
- Network security software interfering with DNS requests
- Incorrect server-level security rules
When DNS traffic is blocked, the server appears unresponsive even if it is online.
Why These Errors Are Often Misleading
A DNS server not responding message does not always clearly explain the root cause. The problem could be:
- At the domain or DNS provider level
- On the web or email server
- Within the user’s network or device
Without proper checks, it is easy to troubleshoot the wrong area and waste time.
