Proxy PAC file accessed using UNC path works in Chrome, IE8... but not IE9


All replies

  • Hi,

    Anyone to help me?


    Thank you in advance


    Tuesday, September 25, 2012 7:01 AM
  • Hi,

    Based on my research, please add the automatic configuration feature control key and see how it works.

    1. Click Start, type regedit in the Start Search box, and then press Enter.

    2. Locate and then click the following registry subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main\FeatureControl

    3. On the Edit menu, point to New, and then click Key.

    4. Type the following key name, and then press Enter:


    5. On the Edit menu, point to New, and then click DWORD Value.

    6. Type iexplore.exe, and then press Enter.

    7. Right-click iexplore.exe, and then click Modify.

    8. In the Value data box, type 1, and then click OK.

    9. Exit Registry Editor.

    More information: Automatic Configuration

    However, if issue persists, as all the related documents only mention URL instead of UNC path, I’m afraid that UNC path is not supported or it does not the best practice.

    Hope this helps.

    Jeremy Wu

    TechNet Community Support

    Tuesday, September 25, 2012 8:52 AM
  • Hi,

    Thank you for the answer.

    In fact, I saw some of the javascript in this file was not fully compatible with IE9... After reviewing it and modifying some info, it worked well with the following syntax to load the file:


    Thank you


    Thursday, September 27, 2012 4:44 AM
  • Hi, we are experiencing the same issue, I have copied the proxy.pac file onto an internal web server that is reachable via DNS and it works in Firefox and chrome, but not in IE 9any help would be gratefully received:

    function FindProxyForURL(url, host) {

    var resolved_ip = dnsResolve(host);
    if (isInNet(resolved_ip, "", "") ||
        isInNet(resolved_ip, "", "") ||
        isInNet(resolved_ip, "", "") ||
        isInNet(resolved_ip, "", ""))
    return "DIRECT";

    // If the protocol or URL matches, send direct.
        if ((url.substring(0, 6)=="https:") && (isInNet(myIpAddress(), "", "")))
            return "PROXY";
        if ((url.substring(0, 5)=="http:") && (isInNet(myIpAddress(), "", "")))
            return "PROXY";
    return "DIRECT";

    Tuesday, November 05, 2013 3:15 PM