Windows 10: Pac/Wpad file not ready correctly by Edge/IE or Chrome

Hi All,


We have a WPAD.dat file that has been used and works fine internally on all of our local network. But on VPN, it doesn't work correctly. We have enabled split tunneling on the firewall and when I connect to the VPN, I obtain the address on the 10.201.50.x range. Instead of going out 'DIRECT' as the line in the code shows, it skips this and goes down to the default rule which is to go out via the Proxy. I have tried everything and I'm reading that it is highly likely the myIpAddress function is the issue? I've even tried prioritising the metric settings by using powershell to prioritise the VPN adapter, but still nothing. Can you help me? I'm using Edge version 87.0.664.75.


function FindProxyForURLurl, host {

//url = url.toLowerCase;

//host = host.toLowerCase;



// If the hostname matches, send direct.

if dnsDomainIshost, ".contoso.co.uk"

shExpMatchhost, "*.contoso.co.ukcontoso.local"

return "DIRECT";





// If the requested website is hosted within the internal network, send direct.



if isPlainHostNamehost

shExpMatchhost, "*.local"

isInNetdnsResolvehost, "10.0.0.0", "255.0.0.0"

isInNetdnsResolvehost, "172.16.0.0", "255.240.0.0"

isInNetdnsResolvehost, "192.168.0.0", "255.255.0.0"

isInNetdnsResolvehost, "173.37.0.0", "255.255.0.0"

isInNetdnsResolvehost, "127.0.0.0", "255.255.255.0"

return "DIRECT";



if isInNetmyIpAddress, "10.201.50.0","255.255.254.0"

return "DIRECT";


// DEFAULT RULE: All other traffic, use below proxies, in fail-over order.

return "PROXY 10.215.0.230:8080; DIRECT";


}


Thank you

Yashy99

:)

 

wpad issues

I have an odd issue that i am unable to track down sort out. Have put this under windows instead of IE11 because it seams to stem from windows internet options.

In our business we have a very long proxy.pac file because there are internal domains that are only reachable via specific proxies they are not publicly resolvable. One of these sites is old and runs on aspx so requires IE (we are migrating it along eventually)

Across multiple devices Edge(chromium) or chrome the wpad lookup works correctly and the site opens, unfortunately it doesn't function correctly (aspx)

However on some devices when opening in IE11 it works fine.

On another subset we get DNS not found, as thou it is totally skipping the wpad process.

Another interesting side effect on these hosts that don't work if we try to open URLs in edge that are not FQDN ie http://internalsite (which is also http://internalsite.internaldomain)

We get

No authority could be contacted for authentication

unless we go to local intranet zone and check Automatically detect intranet network (on the other set of devices that IE11 works fine this doesn't need to be checked)

We are awkwardly in a split domain network (in transition) so these sites would normally use NT login (sharepoint) however these devices are no longer part of that domain so we have to authenticate domain1\username when the login pops up.

We have tried disabling AutoproxyResult cache (https://support.microsoft.com/en-au...-automatic-proxy-caching-in-internet-explorer)

wpad override (Proxy Auto Detect (WPAD) Issues With IE & Windows 7)

The wpad key is empty otherwise not showing a cached entry that i can see.

Now if i manually set the proxy statically ie http://wpad/wpad.dat it works fine, but this obviously breaks the host when we move backwards and forward between on VPN and off VPN.

Have checked the dev console (F12) however this doesn't show the pre GET/CONNECT process.

I'm also in a situation that currently devices are at home, so wireshark to check what dns lookups occur for wpad are encrypted out the interface so no idea if the lookup fails, but given nslookup from cmdline wpad resolves, wpad.internaldomain resolves
and http://wpad/wpad.dat works i'm a bit lsot.

It's like something has told it to skip the wpad process in IE11 but works fine in edge, or something wrong with resolution of internaldomain stuff.

This is on different identical hardware and fresh installs, we have only been on this platform for a few weeks overall so devices are very fresh.

 

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Again, using https://someserver/script.pac does NOT work. Using http://someserver/script.pac works.

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