1) Use Google Chrome as the default browser for the time being, and temporarily bypass using a proxy server if you are using one:
Go to "Control Panel" > "Network And Sharing Center" > "Internet Options" > "Connections" tab -> click on the "LAN Settings" button > uncheck "Use a Proxy server..."

2) Disabled proxy in Windows 10: -
https://answers.microsoft.com/en-us/insider/forum/insider_wintp-insider_web/windows-10-build-9879-proxy-server-settings/d7bbc6dd-5539-4e68-93c1-9401468701b5?auth=1

3) Ensure the following registry value is set to 0:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ProxyEnable

4) Disable "Use automatic configuration script", under Internet Properties > Connections > LAN Settings.