If the previous method does not help in resolving the DNS server error in your Windows device, you can move to the next solution. You will probably get this error because of the cache developed in the Windows device. So, to resolve it, you need to remove the cache from your computer. Also, you will require to reset the IP. For that, you can follow the instructions right here.
If you are still unable to fix the DNS server error, then you should try this method. When you use the outdated version of the network adapter in your device, it causes some issues. So, if you have not upgraded your network adapter driver, then you might get the DNS server error notification and fail to connect to the internet.
Therefore, you can check if you using the latest version of the Network Adapter Driver in your Windows device or not. Like every other system drivers in your device, the Network Adapter Driver also requires a periodical update to maintain the compatibility with your device. Hence, when you do not upgrade it, it becomes obsolete and loses its compatibility with your Windows device.