Why do I see "This site can't be reached" only on my device, not everyone else's?

If a website opens for other people but you get "This site can't be reached", the site is almost certainly not down: something is stopping only your connection. In most cases it's a stale DNS cache, your internet provider's DNS, a VPN, antivirus or browser extension, or the site's firewall blocking your IP address. The grey code under the message (for example ERR_NAME_NOT_RESOLVED) usually tells you which of these to check first.

It's a scary moment, especially when it's your own business site and a friend on the phone says "it opens fine for me". Below is the order we use ourselves: confirm it really is only you, read the error code, then work through the usual suspects from the quickest fix to the rarest. You don't need to be technical for any of it.

First: make sure it really is only you

Don't rely on a single friend. They might have the same problem by coincidence, or be on the same network as you.

• Open the site on your phone using mobile data, not your home or office Wi-Fi. If it works on data but not on Wi-Fi, the problem is in that network, its router or its internet provider.
• Ask two or three people on different networks, ideally in different cities, to try.
• Use a free checker such as downforeveryoneorjustme.com. It tries to load your address from outside your network and tells you whether the server answers.

If other people and the checker can open the site, the server is alive. From here on, the problem is on your side, not the site's.

Narrow it down: change one thing at a time

Each test below changes a single thing. The first one that makes the site appear points straight at the cause.

What the error code under the message tells you

Under the main message on its error page, Chrome shows a short code in grey capital letters. Read it before you change anything: it separates "I can't find the address" problems from "I found the address but couldn't connect" problems. Other browsers word their error pages differently, but the causes are the same.

A simple rule of thumb: if the code mentions NAME or DNS, start with the DNS sections below. If it says TIMED_OUT and the site opens fine on mobile data, go straight to the section about a blocked IP address.

Cause number one: a stale DNS cache

DNS is the internet's phone book: it turns your-address.com into a numeric IP address (more on that in what DNS is, in plain language). Your browser, your computer and often your router remember the answer for a while, to be faster. The trouble starts when the site has moved to a new server (a new IP) and you still have the old address saved. Everyone else, who had nothing saved, goes straight to the new one.

Clear the cache, from the quickest step to the most thorough:

• In the browser: open the site in an Incognito window, or reload while skipping the cache with Ctrl+Shift+R (Cmd+Shift+R on Mac).
• Chrome's own DNS cache: type chrome://net-internals/#dns in the address bar and click Clear host cache.
• Windows: search for "cmd" in the Start menu, open Command Prompt and type ipconfig /flushdns.
• Mac: open Terminal and type sudo killall -HUP mDNSResponder, then enter your Mac password. Nothing is printed when it works; that's normal.
• Restart your router. Many home routers keep their own copy of DNS answers, and a restart clears it.

Then close the browser completely, open it again and retry. Most of the time, this is where it gets solved.

When your provider's DNS is to blame

If you've cleared the cache and it still won't load, the next suspect is the DNS server you're using, usually the one your internet provider assigns automatically. Sometimes it's slow, misconfigured, or still serving an old answer for your domain.

Quick test: temporarily switch your DNS to a public one, such as 1.1.1.1 (Cloudflare) or 8.8.8.8 (Google). If the site appears after the switch, your provider's DNS was the problem.

• Windows 11: Settings > Network & internet > Wi-Fi or Ethernet, open your connection's properties, change the DNS setting from Automatic to Manual, turn on IPv4, enter 1.1.1.1 as Preferred DNS and 8.8.8.8 as Alternate DNS, then Save.
• Mac: Apple menu > System Settings > Network, choose your connection, click Details, then DNS, and add the addresses with the + button (Apple's guide).
• Router: changing DNS on the router fixes it for every device in the house, but the menu differs from model to model, so check its manual.

Chrome can also use its own DNS, separate from your system. Go to Settings > Privacy and security > Security and, under "Advanced", look at Use secure DNS. If a custom provider is selected and that provider has problems, Chrome won't fall back to your normal DNS, so the site can fail in Chrome while it opens in other browsers (Google's help page). To test, switch back to your current service provider or turn Use secure DNS off.

A block can also come from the network itself: parental controls or a family-safe filter on the router, or the rules of an office, school or hotel Wi-Fi. These only affect that one network, which is exactly the "works on mobile data, not on Wi-Fi" pattern.

Finally, an internet provider can actually block an address (rare, but it happens). If the site works over a VPN or on mobile data from a different carrier, but not on your fixed connection, and changing DNS didn't help, the block is at the provider or on your IP, not on your device and not on the site.

When the site's firewall has blocked your IP address

This one catches a lot of site owners out. Many hosting servers run a firewall that automatically blocks an IP address after repeated failed logins, whether to email, FTP, the hosting control panel or the site's admin area. Once your IP is on that list, the site simply stops answering you, while it works for everyone else.

A common pattern: someone changes the company email password, but an old phone or laptop in the office keeps trying the old one in the background. The server sees failed logins coming from your office connection and blocks it.

The signs:

• The error is ERR_CONNECTION_TIMED_OUT (sometimes REFUSED), not a DNS error.
• It fails on every device on the same Wi-Fi, but works on mobile data or over a VPN.
• Switching DNS changes nothing.
• If your email is hosted on the same server, it often stops working on that connection at the same time.

What to do: find your public IP address (search "what is my IP"), send it to your hosting provider's support and ask them to check the firewall and unblock it. Then fix the device with the wrong password, or the block will come back. If the site sits behind a CDN or uses a security plugin, check its block list too, although those usually show an "access denied" page rather than a connection error.

Local suspects: the hosts file, antivirus, extensions, VPN

Sometimes neither the provider nor the server is at fault, but something on your own computer is.

• The hosts file: a system file that can force a domain to a specific IP. If it points to the wrong one, only you see the error. On Windows it's at C:\Windows\System32\drivers\etc\hosts, on Mac at /etc/hosts. A classic leftover after a site move: a line added to preview the new server and never removed. You need administrator rights to edit it: on Windows, run your text editor as administrator; on a Mac, open it from Terminal with sudo nano /etc/hosts. Look for lines containing your domain and put # at the start of them to switch them off.
• Antivirus or firewall: some security suites block sites they wrongly consider dangerous. Temporarily disable web protection, test, and if that was it, add the site to the allowed list instead of leaving protection off.
• Browser extensions: an overly aggressive ad blocker or VPN extension can stop a site loading. Test in Incognito, where extensions are off by default.
• An active VPN or proxy: if you have one running, turn it off and retry.

If the site appears in Incognito, with no VPN and the antivirus paused, you've found the culprit.

When it only fails on your phone

• Turn off any VPN or ad-blocking app and try again.
• Android: open Settings > Network & internet > Private DNS (on some phones it sits under connection or advanced network settings). If it's set to a specific provider hostname, switch it to Automatic or Off to test (Android help).
• iPhone: iCloud Private Relay hides your IP address, and Apple notes that sites relying on IP filtering may block you while it's on. In Safari, tap the Page Menu button, then Show IP Address to reload without it, or go to Settings > Wi-Fi, tap the More Info button next to your network and turn off Limit IP Address Tracking (Apple's guide).

If you've just moved the site or changed its DNS

Right after a move, it's normal for some people to see the new server while others (maybe you) still reach the old one, or nothing at all. The change spreads as caches around the internet expire. Cloudflare's documentation says nameserver changes typically take anywhere from a few minutes to 48 hours, often much less when the TTL (how long an answer may be cached) was lowered beforehand.

• Clear your own caches as described above.
• Ask the big public resolvers to refresh your domain: Google Public DNS has a Flush Cache tool and Cloudflare has a Purge Cache tool for 1.1.1.1.
• Check the hosts file for a preview line pointing to the old or new server.
• Use a DNS propagation checker (search for one) to see which IP address different parts of the world currently get for your domain.

How to tell it's actually a real outage

Not everything that errors is your fault. These are the signs the problem really is on the site or its hosting:

• The external checker also reports the site as down.
• Nobody, on any network, can open it.
• Everyone gets DNS_PROBE_FINISHED_NXDOMAIN: that can mean the domain has expired or been suspended, or its DNS records are missing.
• You see different messages, not "This site can't be reached": a 500 error, "Error establishing a database connection" or a blank page. Those come from the server, not your connection (see what a 500 error means and why a site goes down).
• The SSL certificate has expired ("Your connection is not private"), which affects everyone.

One exception: a page saying "Access denied" or "You have been blocked" is not an outage. It's a security rule blocking your IP, and the fix is the same as in the firewall section above.

In these cases, contact the company that hosts your site. If you work with us at MPO Web Studio, message us on WhatsApp and we'll check the server, DNS and firewall for you. We handle maintenance remotely, so it doesn't matter where you are. A well-built site should also have uptime monitoring, so you hear about an outage before your customers do.