github and many other websites connot be reached

Question

After i reset my laptop that has windows 10 as operating system some sites is not opening, the problem is github which i depend on mainly , i tried flush dns , changing dns , removing chrome and firfox, changing their settings as mentions on many wesites with no avail ,i dont have a proxy installed or any vpn , i changed laptop mac address , tried vpn .... no solution availed me ,i am worry that i have to format and reinstall windows 10 , please feel free to offer any solution

Answer 1

To properly debug this the best thing to do is to classify where the problem occurs, this could be at many layers

• DNS Resolution
• IP/ Basic Networking Level
• Firewall
• TCP

Now in your post you mention that some sites are not working, from that I will make an assumption that others are working. So the first thing to look at is whether DNS Resolution works. The best way on Windows to check DNS Resolution as well as basic network connectivity is via the following PowerShell Commands :

The Following will tell you if you can resolve the Name and give you an IP address

Resolve-DnsName GitHub.com

The Following will tell you if you have Network Connectivity to the site

Test-NetConnection GitHub.com -CommonTCPPort HTTP
Test-NetConnection 192.30.255.112 -CommonTCPPort HTTP

If all of these succeed the next stops are TCP and Firewall Layers. To get logs for those you can try the following

Netsh wfp Capture start
<Try Accessing GitHub.com> 
netsh wfp capture stop

Open the XML file in the Cab and you can check if there was a classify drop for the GitHub IP Address.

For TCP Logs you can collect them via

netsh trace start scenario=InternetClient_dbg capture=yes persistent=yes
<repro>
netsh trace stop
Share nettrace.cab