A name lookup times out, but a TCP test succeeds. What does that tell you?

Instruction: Explain what each result does and does not establish. Choose read-only Windows diagnostics that separate name resolution, network reachability, and application behavior.

Context:

A Windows 11 user cannot open https://inventory.corp.example. The application owner confirms that 10.40.20.15 is the current approved endpoint. Fictional diagnostic excerpts:

Configured DNS servers: 10.40.0.10, 10.40.0.11
Resolve-DnsName inventory.corp.example -Server 10.40.0.10 -DnsOnly
  Error: This operation returned because the timeout period expired.
Test-NetConnection 10.40.20.15 -Port 443
  TcpTestSucceeded: True
ping 10.40.0.10
  Request timed out. (4 requests)

No browser test by IP has been performed. You are authorized to run read-only diagnostics against these company endpoints, but not change DNS or firewall policy.

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I'd explain that the DNS query timed out while the approved endpoint accepted a TCP connection on port 443. That narrows the problem, but neither result establishes whether the inventory application works. I'd preserve the current settings and compare the configured company resolvers before choosing a repair, using the same hostname and a working device where available...

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