Hello Bleeping Computer and thank you again for your help!
I have a computer running Windows 10 x64 and today, suddenly, it couldn't resolve DNS. I could connect to my local access point. Other devices connected to the access point could resolve DNS and connect to the internet. First, I tried restarting the computer. Alas, no change.
Then, I checked my wireless driver properties, disabled IPv6 (it was enabled) and changed IPv4 from Automatically Resolve DNS to the following: primary DNS 18.104.22.168; secondary DNS: 22.214.171.124 . I have the same configuration on a Windows 7 machine and it works just fine (again, same access point).
Well, that didn't work. I tried to flush the DNS cache using by running a command prompt with admin priviledges and typing "ipconfig /flushdns" . That returned "Windows IP Configuration" and stayed there. I waited a few minutes and nothing happened so I CTRL+C out of there. Then, I tried "ipconfig /registerdns". That returned the same "Windows IP Configuration". Then, I tried "net stop dnscache" that gave returned (wording may be slightly different as I am translating) "The service is not responding to the control function. You can get more help with the command NET HELPMSG 2186." So, I typed NET HELPMSG 2186 and it returned "The service is not responding to the control function."
I started getting suspicious. This has never happened before. I checked Windows Update and the last update was on 4/10/2018 (a week ago) and the computer has been working just fine the past few days.
I started getting suspicious and I ran "netstat -an" to see the network traffic. This was after I had been disconnected from the access point for a few minutes. It showed A REMOTE ESTABLISHED CONNECTION. It was TCP connection (ESTABLISHED), connecting to the local port 63515 and connected to a remote IP port 443. I looked up the IP and it is registered to Amazon. I can provide the IP if you would like. This seemed like malicious behavior so I also reported it to Amazon.
I am downloading the network drivers for the machine, but will wait for your response before I do anything further. Am I infected? What should I do?