Forward proxy with PAC file

i'm deploying barracuda forward proxy.  i've got cuda setup, , if plug in proxy address in ie manually, works , cuda redirects/blocks specified categories , websites want.

now, want deploy forward proxy settings via windows group policy.  laptops, needed way go out internet direct when outside network otherwise couldn't surf web.

research has led me configure pac file via gpo when users laptops outside network , can't communicate proxy, browser go out internet direct.  can't pac file work.  hoping else has run or has tips point me in right direction.  know ideally configure web site in lan , store pac file on browser (basically).  know there more configure such setting mime types, etc...  right i'm trying pac file work local file , isn't working.  here is pac file examples i've tried:

examples:

function findproxyforurl(url, host) {
 
 if (isinnet(myipaddress(), "192.168.15.0", "255.255.255.0"))
  return "proxy 10.192.34.74:8080";
  return "direct";    
}

or even

function findproxyforurl(url, host)
{
      return "proxy 10.192.34.74:8080; direct";
}

configuring ie internet options "use automatic configuration script" , setting address file://c:/proxy/proxy.pac.  proxy.pac file on local computer in c:\proxy\proxy.pac.  proxy in different subnet lan pingable , have vpn 10.192.34.74 network.  don't know missing....can provide input?

1. discovered ie 9 ignores local pac files. using local pac file test, must point ie 9 pac file on web server. also, in testing must use resolvable dns name in automatic configuration script. me pointing ie http://local ip address/proxy.pac did not work.

2. must save pac file ansi. if file saved unicode ie doesn't it. open pac file in notepad , chose file type ansi.

3. make sure web server has mime type application/x-ns-proxy-autoconfig .pac extension.

after confirmed pac file working great in ie 9 , ie 8.

Windows Server  >  Group Policy