Modify the Host file
# Github 151.101.44.249 github.global.ssl.fastly.net 192.30.253.113 github.com 103.245.222.133 assets-cdn.github.com 23.235.47.133 assets-cdn.github.com 203.208.39.104 assets-cdn.github.com 204.232.175.78 documentcloud.github.com 204.232.175.94 gist.github.com 107.21.116.220 help.github.com 207.97.227.252 nodeload.github.com 199.27.76.130 raw.github.com 107.22.3.110 status.github.com 204.232.175.78 training.github.com 207.97.227.243 www.github.com 185.31.16.184 github.global.ssl.fastly.net 185.31.18.133 avatars0.githubusercontent.com 185.31.19.133 avatars1.githubusercontent.com 192.30.253.120 codeload.github.com
Refresh DNS, type the following command in the toolbar
ipconfig /flushdns