We have recently rolled a proxy server and deployed utilising a WPAD.dat file, We want to use the DNS deployment method as it will work for all devices then even with a static IP
This file is hosted on am IIS7/Windows server 2008 R2 web server and is able to be accessed by wpad.ourinternaldomain.com
However, On certain computers, and across our servers, if you open internet explorer you immediately get a prompt for credentials which is coming from the web server the wpad file is hosted on as the heading of the prompt is "Connecting to "webserver"
Mostly users do not see this however some are, and on our servers when doing various tasks requiring access to web GUI's it is quite frustrating.
Entering the full address (http://wpad.domain.com/wpad.dat) into the browsers auto configuration field immediately produces a user and password prompt hwne pressing ok to save those settings in IE.
If i enter this address on my PC to attempt to download the file, i also get prompted for a user and password, yet on my PC the "auto configuration" is working fine!
on the IIS server we have allowed anonymous auth and ensured the directory security is setup for all authenticated users.