Fix 'DNS server not responding' in 30 seconds or less

The 30-second fix: restart your router and modem

I know, it sounds like the old "turn it off and on again" joke. But I've seen this fix work more times than I can count. Had a client last month whose entire office lost internet for two hours because nobody tried this first.

Unplug both the power cables from your modem and your router. Wait 30 seconds. Plug the modem back in first, wait for all lights to go solid, then plug in the router. That forces both devices to grab fresh DNS settings from your ISP. Nine times out of ten, that's all you need.

If you're on a laptop or desktop, also restart your computer after the router is back up. Sometimes Windows holds a stale DNS cache that still points to the old server.

The moderate fix (5 minutes): flush your DNS cache and renew your IP

If restarting didn't work, your computer's DNS cache might be corrupted or pointing to a dead server. I've seen this happen after a Windows update, a VPN disconnect, or even a power surge that screws up network stacks.

Open Command Prompt as administrator (hit the Start button, type cmd, right-click it, choose "Run as administrator"). Then run these commands one at a time:

ipconfig /flushdns
ipconfig /registerdns
ipconfig /release
ipconfig /renew
netsh winsock reset

Press Enter after each command. The flushdns clears everything your computer remembers about DNS lookups. The release and renew force your computer to ask the router for a new IP and DNS server addresses. The netsh winsock reset fixes the Winsock catalog – I've seen this specifically fix DNS errors on Windows 10 and 11 after a bad driver update.

After all that, restart your computer. Test by opening a website. If it works, you're golden. If not, move to the next step.

The advanced fix (15+ minutes): change your DNS server manually

Sometimes your ISP's DNS servers are just bad. I've had clients where Comcast or Spectrum DNS would randomly fail for 15 minutes at a time. Switching to a third-party DNS server fixes this permanently.

Step 1: Set a static DNS in Windows

1. Press Win + R, type ncpa.cpl, hit Enter. That opens Network Connections.
2. Right-click your active network adapter (usually Ethernet or Wi-Fi), choose Properties.
3. Select Internet Protocol Version 4 (TCP/IPv4), click Properties.
4. Select "Use the following DNS server addresses".
5. For primary DNS, put 8.8.8.8 (Google). For secondary, put 1.1.1.1 (Cloudflare). Or swap them – I use Cloudflare primary, Google secondary. Both are fast and reliable.
6. Check "Validate settings upon exit" – Windows will test the connection.
7. Click OK, close everything, restart your computer.

Step 2: Update your router's DNS (optional but better)

If you change DNS on your router instead of each PC, every device in the house gets the fix. I do this for all my clients. Here's how:

1. Log into your router's admin panel (usually 192.168.1.1 or 192.168.0.1 – check the sticker on the router).
2. Find the DNS or Internet Setup section. It's under "WAN" or "Internet" on most routers.
3. Change DNS from "Get from ISP" to manual; enter 1.1.1.1 and 8.8.8.8.
4. Save, reboot the router.

I've seen routers with DNS settings buried under "Advanced" or "Administration" – don't be afraid to click around. If you can't find it, check the manual PDF online.

When to call your ISP

If none of this works after 15 minutes, your ISP might be having a regional outage. I had a client in Cleveland where the entire neighborhood lost DNS for two hours because a construction crew cut a fiber line. Check downdetector.com or ask a neighbor. If they're also down, it's not your gear – call your ISP and wait it out.