"Server not found" problem on FF 39, Win 7

MATE - 64bit will work alright.

I booted from Linux Mint - and everything went smoothly. Pages are loading fast and there weren't any Server not found message.
Just opposite of Win7

Alright, that rules out any hardware fault.

Create a manual System Restore point - System Restore
Download and run as admin - Download Complete Internet Repair - MajorGeeks
Select options:
- Reset Internet Protocol
- Repair Winsock
- Renew Internet Connections
- Reset Windows Firewall Configuration

I did it. So far, so good...but let's wait a day or two. I'll mark the thread a s solved then.
Thank you.

I just turned my PC on and...(sigh) the problem is still here. I get the same message ("The connection has timed out" this time)
Troubleshooter is diagnosing the issue: "Your computer appears to be correctly configured, but the device or resource (DNS server) is not responding"
I do not know why DNS server is not responding after all this resetting and renewing and everything...

The connection has timed out

Is it still like this?

Try run in cmd when you are getting the above error.

Code:

ping 8.8.8.8

I will. I have 2 LAN ports built in on the motherboard. Only one of them is active at a time, of course, but perhaps it has something with this problem. Today I hadn't any "The connection has timed out" messages, only slow loading of pages. However, when the first such message appears I'll try that command and post the results.

OK, "The connection has timed out" message still appears occasionally.
I ran the command and here are the results copied from cmd:

C:\Windows\system32>ping 8.8.8.8

Pinging 8.8.8.8 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Ping statistics for 8.8.8.8:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

C:\Windows\system32>^A

Download the driver for Network adapter that has the cable plugged in. In Device Manager expand Network Adapters. Right click the one that is plugged in - Uninstall Driver - tick "Delete the driver software.." too. Restart PC, let Windows find the correct driver. If it can't use the driver you downloaded.

I've tried that solution already. I tried it again, but to no avail.
GokAy, after all these posts, it may appear like I am pulling your leg, but I am not. I am grateful to you for trying to help me but perhaps this is unfixable.