Yeah, that error is a pain. But it's usually a quick fix. Here's what I do on every client machine that shows up with it.
The Fast Fix: Flush and Switch DNS
Open Command Prompt as Administrator. On Windows 10 or 11, hit Start, type cmd, right-click and choose Run as administrator. Then run these two commands:
ipconfig /flushdns
netsh winsock resetReboot the machine. That alone solves a chunk of cases – especially if the error started after a VPN disconnect or a sleep/wake cycle.
If it's still showing up, change your DNS server. Go to Network Settings → Change adapter options → right-click your active adapter → Properties → select Internet Protocol Version 4 (TCP/IPv4) → Properties. Set it to use these addresses:
Preferred DNS: 8.8.8.8
Alternate DNS: 8.8.4.4Or use Cloudflare's 1.1.1.1 if you prefer. Either works. Click OK, close everything, then try the site again.
Why This Works
Your computer caches DNS lookups to speed things up. That cache goes stale – a site moves servers, an old entry sticks around, and your browser gets pointed at a dead address. Flushing clears that junk. Changing to a public DNS bypasses your ISP's resolver, which might be having its own issues. I had a client last month whose entire office couldn't reach their own website, and it turned out their ISP's DNS server was down. Switching to Google fixed it in two minutes.
Less Common Variations
Hosts File Hijack
Sometimes the problem is local. Open Notepad as admin, then open C:\Windows\System32\drivers\etc\hosts. Look for lines with the site's domain name that aren't commented out (no # at the start). If you see something like 127.0.0.1 example.com, that's blocking it. Delete that line, save, flush DNS again.
Router Cache
Your router also caches DNS. Unplug it for 30 seconds, plug it back in. That clears its cache. Do this before you call your ISP – most of their front-line scripts won't tell you this.
VPN or Proxy Interference
If you're on a VPN, disconnect and test. Some VPNs route DNS through servers that go down. Also check Windows proxy settings – Settings → Network & Internet → Proxy. Make sure "Use a proxy server" is off unless you're in a corporate network that requires it.
Malware or Browser Extensions
Rare, but possible. Run a Malwarebytes scan. Also try incognito mode – if the site loads there, an extension is the culprit. Disable extensions one by one.
Prevention
Keep your DNS set to a public resolver permanently. It's not just for fixing errors – it's usually faster than ISP DNS anyway. Also schedule a weekly reboot of your router. And if you're on Windows, clear your DNS cache regularly:
ipconfig /flushdnsThat's it. Do that, and you'll rarely see this error again. If it still happens after all these steps, then it's the site itself – check with ping or use an online DNS checker to confirm the domain resolves globally.