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static function OnAttach() {
    UpdateWinHTTPSettings();
}
static function OnDetach() {
    UpdateWinHTTPSettings();
}

static function UpdateWinHTTPSettings() {
    var oPSI: System.Diagnostics.ProcessStartInfo
        = new System.Diagnostics.ProcessStartInfo();
    var os : OperatingSystem = Environment.OSVersion;
    if (os.Version.Major >= 6) {
        oPSI.UseShellExecute = true;
        oPSI.FileName = "netsh.exe";
        oPSI.Verb = "runas";
        oPSI.Arguments = "winhttp import proxy ie";
        System.Diagnostics.Process.Start(oPSI);

        // Re-run 32bit version
        oPSI.FileName = oPSI.FileName =
            Environment.SystemDirectory.Replace("system32", "syswow64")
            + "\\netsh.exe";
        if (System.IO.File.Exists(oPSI.FileName)) {
            System.Diagnostics.Process.Start(oPSI);
        }
    }
    else {
        oPSI.UseShellExecute = true;
        oPSI.FileName = "proxycfg.exe";
        oPSI.Verb = "open";
        oPSI.Arguments = "-u";
        System.Diagnostics.Process.Start(oPSI);
    }
}