I had encountered this the hard way some months ago, but today I was Googling on this to share the same with a colleague. Starting with IE 11 you cannot use file server locations (e.g.
\\mydomain\dfs\global.pac) for the PAC file. You have to use an HTTP or HTTPS location (e.g.
It is possible to change a registry key to enable this behavior. This and other nuggets of info can be found in this wonderful MSDN article on web proxy configuration.
- There’s WinINET and WinHTTP proxy settings. WinINET is the one you set via IE. WinHTTP is the one you set via
netsh winhttpI think.
- Firefox uses the WinINET settings if set to use system proxy settings.
- Proxy settings are per user, but can be changed via a registry key to be for all users of a machine.
- Automatically detect settings looks for the
wpad.<domainname>entry or uses DHCP to get a proxy script URL.