4
DNS
4 NOTIMP
Not Implemented. The name server does not support the requested query type or operation.
On this page
When You See This Code
You sent a query type (e.g., IXFR, dynamic update) that the server does not support or has disabled.
How to Fix
Verify the server supports the query type you are using. If you need zone transfers or dynamic updates, enable them in the server configuration.
Specification
Compare With
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HTTP Fundamentals
Step-by-Step DNS Troubleshooting with dig and nslookup
Debugging & Troubleshooting
Improving Email Deliverability: SPF, DKIM, and DMARC Setup
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DNS Response Codes (RCODEs) Explained
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DNSSEC Implementation Guide
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Resource Hints: Preload, Prefetch, Preconnect, and DNS-Prefetch
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RFC 9114: HTTP/3 Protocol Deep Dive
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RFC 3261: SIP Protocol Deep Dive
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QUIC Protocol: The Transport Layer Behind HTTP/3
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Frequently Asked Questions
What is DNS 4 NOTIMP?
Not Implemented. The name server does not support the requested query type or operation.
When do you see DNS 4 NOTIMP?
You sent a query type (e.g., IXFR, dynamic update) that the server does not support or has disabled.
How to fix DNS 4 NOTIMP?
Verify the server supports the query type you are using. If you need zone transfers or dynamic updates, enable them in the server configuration.