C# program causes bluescreen?

Question

This is only the important stuff that the bluescreen shows. I'm on Windows 7 x64.

"A problem has been detected and Windows has been shut down to prevent damage to your computer.

PROCESS_HAS_LOCKED_PAGES

* STOP: 0x00000076 (0x0000000000000000, 0xfffffa8009dcd060, 0x0000000000000011, 0x0000000000000000)"

I can't work on it now because every time I close it I get a bluescreen! The program doesn't do anything yet except run the background worker below. It pings all addresses that could be part of the user's home network and attempts to connect to a certain port that another program will be listening on.

private void NetworkScanner_DoWork(object sender, DoWorkEventArgs e)
    {
        bool ExceptionEncountered = false;
        int IPsProcessed = 0;

        NetworkSearcherOutput = "Starting network scanner...";
        NetworkSearcher.ReportProgress(0);
        Thread.Sleep(1000);

        foreach (IPAddress IP in Dns.GetHostAddresses(Dns.GetHostName()))
        {
            if (IP.AddressFamily == AddressFamily.InterNetwork)
            {
                string[] Octets = IP.ToString().Split('.');
                Octets[3] = "0";

                IPAddress CurrentAddressIteration = StringArrayToIP(Octets);
                while (GetLastOctet(CurrentAddressIteration) != 255)
                {
                    PingReply Reply = new Ping().Send(CurrentAddressIteration, 5);

                    if (Reply.Status == IPStatus.Success)
                    {
                        NetworkSearcherOutput = CurrentAddressIteration.ToString() + " sent response.";
                        NetworkSearcher.ReportProgress(0);
                        Thread.Sleep(500);

                        InClient Client = new InClient(CurrentAddressIteration);

                        try
                        {
                            Client.Connect();

                            SnapshotBox.Image = Client.Receive(typeof(Image));

                            NetworkSearcherOutput = CurrentAddressIteration.ToString() + " is running program.";
                            NetworkSearcher.ReportProgress(0);
                            Thread.Sleep(1000);
                        }

                        catch (Exception E)
                        {
                            // A socket exception is expected when the client is not running the program.
                            if (E is SocketException)
                            {
                                Client.Close();

                                NetworkSearcherOutput = CurrentAddressIteration.ToString() + " is not running program.";
                                NetworkSearcher.ReportProgress(0);
                                Thread.Sleep(1000);
                            }

                            //Unhandled exception. Show messagebox and close.
                            else
                            {
                                MessageBox.Show("Network scanner encountered an unhandled exception.\n\n" + E.GetType().ToString() + ": " + E.Message, "Unhandled Exception", MessageBoxButtons.OK, MessageBoxIcon.Error);
                                ExceptionEncountered = true;
                                break;
                            }
                        }
                    }

                    else
                    {
                        NetworkSearcherOutput = CurrentAddressIteration.ToString() + " did not respond.";
                        NetworkSearcher.ReportProgress(0);
                    }

                    IPsProcessed++;

                    if (IPsProcessed == 5)
                    {
                        NetworkSearcher.ReportProgress(2);
                        IPsProcessed = 0;
                    }

                    Octets = CurrentAddressIteration.ToString().Split('.');
                    Octets[3] = (Int32.Parse(Octets[3]) + 1).ToString();
                    CurrentAddressIteration = StringArrayToIP(Octets);
                }
            }
        }

        if (!ExceptionEncountered)
        {
            NetworkSearcherOutput = "Network scanning complete.";
            NetworkSearcher.ReportProgress(0);
            NetworkSearcher.ReportProgress(100);
        }

        else
        {
            NetworkSearcherOutput = "Network scanning encountered an error.";
            NetworkSearcher.ReportProgress(-1);
        }

I thought C# programs were supposed to never cause bluescreens?

Answer 1

I discovered this issue a few weeks back. It only happens when using .NET 4.

Reported at MS Connect.

Edit:

(Will*) Add this link to MS Connect bug report.

*login.live.com is going into an infinite loop again...

Answer 2

Just to be clear, there is no way for "user" mode code to forcibly create a blue screen in windows, unless it uses undocumented APIs and or forces bad data into a driver. Your C# code is likely not be at fault here, as if you use the user mode classes (Socket) then the socket is responsible for not crashing your computer.

As @Joe has commented Microsoft Support KB Article 256010 clearly describes this stop message, but better yet has clear instructions on capturing the driver name responsible for this error.

Note that any software firewall that you have installed also is involved at kernel mode level so could also be responsible for this error. I recommend you follow the KB articles advice and try to find out what is at fault. But you could also ensure that you have updated your network drivers and firewall/VPN software to the latest stable versions.