Here are a few steps you can follow to try and resolve the error:
- Restart your router: disconnect from power, wait 10-15 seconds, and then power on the device again.
- Check your cables. Ensure that all necessary cables are securely connected.
- Check your IP address. Sometimes, an incorrect IP address can result in a DNS server not responding error message. To make sure you have the correct address, contact your ISP.
- Check DNS Settings. Make sure that the DNS settings of your router are correct and match those provided by your ISP.
- Flush the DNS cache on your computer. This can help resolve any DNS issues you may be experiencing.