Single User Cannot Resolve Website: Hosts File vs DNS Record
Short answer
A Inspect and correct the local hosts file entry that maps the website's hostname to an incorrect IP address, since other users resolve the site normally.
Question
Key Takeaways
This item tests scope-of-impact reasoning—local-only resolution failure versus shared DNS—and the trap is blaming a nameserver record that would affect every user.
A single user's incorrect website resolution points to a local hosts file override rather than a network-wide DNS nameserver record. The correct answer is A, and the key is isolating the scope of the failure.
Common mistake: Choosing C assumes a nameserver record error, but a shared DNS record fault would typically affect all clients using that resolver, while the symptom here is isolated to one user.
Expert Analysis
Local-only failure is the key clue The decisive detail is scope: one user cannot resolve the website to the correct IP, while other users reach it normally. A single client's resolution path can be changed by a local static mapping, and the hosts file does exactly that—it maps hostnames to IP addresses and is consulted by the client's resolver before normal DNS lookup in common configurations. If that file contains a stale or incorrect entry for the site, the user's browser is sent to the wrong address even though the shared DNS data is healthy. Option A is therefore the most likely cause.
Why the other options do not fit Option B, a self-signed certificate, produces a browser trust warning or certificate error; it does not make the URL return the wrong IP address, and it would not spare other users. Option C, a nameserver record problem, is a server-side or zone-level fault: an incorrect A or AAAA record, delegation, or forwarder would affect every client using that resolver, not only one user. Option D, an IP helper, forwards DHCP broadcasts to a DHCP server; it is unrelated to name resolution for an already-addressed client.
Adjacent decisions the exam expects you to separate The same symptom can move to a shared DNS fault if the scenario changes to all users in the branch or every client using the internal resolver failing while external users succeed. A stale client resolver cache is another local cause, but flushing it is a troubleshooting step, not a listed root cause here. Comments from technicians emphasize that the hosts file is checked before DNS and can be used to override resolution deliberately; one also notes that resolver order is configurable on Linux, so checking local name-service settings matters. The operational consequence of misdiagnosis is real: editing a nameserver record because of one user's hosts entry can cause a broader outage, while overlooking a malicious hosts entry leaves a redirect in place.
Official Reference
- https://www.comptia.org/en/certifications/network/
- https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/reset-hosts-file-back-to-default
These links open the official vendor documentation in a new tab.
Exam Strategy
When a symptom appears on one host, first isolate scope: compare the same URL from another client and query the resolver directly. Local-only failures shift suspicion to client-side artifacts such as the hosts file, proxy settings, or resolver cache before shared DNS records. Read the wording for other users are able—that phrase is a deliberate scope clue and usually eliminates nameserver records, DHCP helpers, and other infrastructure-wide causes.
Frequently Asked Questions
Why does a hosts file affect only one user's website resolution?
What symptom would point to a nameserver record instead of a hosts file?
Does a self-signed certificate cause wrong IP resolution?
Community Votes
100% of anonymous learners picked answer A. Votes are pick records left by other test-takers — they are not the verified answer.
Discussion 5 contributions
Compiled from public community threads and reader submissions, lightly edited for clarity. Handles and vote tallies are shown as recorded, and comments reflect the views of individual contributors.
From public community threads 5
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HeatSquad77 👍 6 Answered AA. hosts file The predecessor to DNS, a static text file that resides on a computer and is used to resolve DNS hostnames to IP addresses. Automatically mapped to a host’s DNS resolver cache in modern systems. The hosts file has no extension.
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chupapi_001 👍 5 Answered AThe hosts file is a local system file that maps hostnames to IP addresses and can override normal DNS resolution . When only one user is experiencing resolution issues while others can access the website normally, this strongly suggests a local configuration problem rather than a network-wide DNS issue.
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chrys 👍 4Hosts file is checked before DNS. It's actually a fun and simple way to hack a system. I had to use it once to keep users from using a PC running an XRAY controller to get on Facebook and other social media sites. Quick 'n' dirty ;-)
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TechieBloke 👍 1 Answered AChrys, Not true, in linux you can choose how to use - you can say first is DNS or no ostfile. No host file at all or no DNS at all.
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Dese_2point71 👍 1 Answered AA. Hosts file
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