Start a windows service and launch cmd

I have gone through all the pain of doing this.

Under windows 7/Vista/2008 it is not possible to load any interactive process from a service – without calling a number of Win API. = BLACK MAGIC

Have a look here and here.

The code below does the trick, use it with your own risk:

public static class ProcessAsCurrentUser
{

    /// <summary>
    /// Connection state of a session.
    /// </summary>
    public enum ConnectionState
    {
        /// <summary>
        /// A user is logged on to the session.
        /// </summary>
        Active,
        /// <summary>
        /// A client is connected to the session.
        /// </summary>
        Connected,
        /// <summary>
        /// The session is in the process of connecting to a client.
        /// </summary>
        ConnectQuery,
        /// <summary>
        /// This session is shadowing another session.
        /// </summary>
        Shadowing,
        /// <summary>
        /// The session is active, but the client has disconnected from it.
        /// </summary>
        Disconnected,
        /// <summary>
        /// The session is waiting for a client to connect.
        /// </summary>
        Idle,
        /// <summary>
        /// The session is listening for connections.
        /// </summary>
        Listening,
        /// <summary>
        /// The session is being reset.
        /// </summary>
        Reset,
        /// <summary>
        /// The session is down due to an error.
        /// </summary>
        Down,
        /// <summary>
        /// The session is initializing.
        /// </summary>
        Initializing
    }


    [StructLayout(LayoutKind.Sequential)]
    class SECURITY_ATTRIBUTES
    {
        public int nLength;
        public IntPtr lpSecurityDescriptor;
        public int bInheritHandle;
    }


    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
    struct STARTUPINFO
    {
        public Int32 cb;
        public string lpReserved;
        public string lpDesktop;
        public string lpTitle;
        public Int32 dwX;
        public Int32 dwY;
        public Int32 dwXSize;
        public Int32 dwYSize;
        public Int32 dwXCountChars;
        public Int32 dwYCountChars;
        public Int32 dwFillAttribute;
        public Int32 dwFlags;
        public Int16 wShowWindow;
        public Int16 cbReserved2;
        public IntPtr lpReserved2;
        public IntPtr hStdInput;
        public IntPtr hStdOutput;
        public IntPtr hStdError;
    }

    [StructLayout(LayoutKind.Sequential)]
    internal struct PROCESS_INFORMATION
    {
        public IntPtr hProcess;
        public IntPtr hThread;
        public int dwProcessId;
        public int dwThreadId;
    }

    enum LOGON_TYPE
    {
        LOGON32_LOGON_INTERACTIVE = 2,
        LOGON32_LOGON_NETWORK,
        LOGON32_LOGON_BATCH,
        LOGON32_LOGON_SERVICE,
        LOGON32_LOGON_UNLOCK = 7,
        LOGON32_LOGON_NETWORK_CLEARTEXT,
        LOGON32_LOGON_NEW_CREDENTIALS
    }

    enum LOGON_PROVIDER
    {
        LOGON32_PROVIDER_DEFAULT,
        LOGON32_PROVIDER_WINNT35,
        LOGON32_PROVIDER_WINNT40,
        LOGON32_PROVIDER_WINNT50
    }

    [Flags]
    enum CreateProcessFlags : uint
    {
        CREATE_BREAKAWAY_FROM_JOB = 0x01000000,
        CREATE_DEFAULT_ERROR_MODE = 0x04000000,
        CREATE_NEW_CONSOLE = 0x00000010,
        CREATE_NEW_PROCESS_GROUP = 0x00000200,
        CREATE_NO_WINDOW = 0x08000000,
        CREATE_PROTECTED_PROCESS = 0x00040000,
        CREATE_PRESERVE_CODE_AUTHZ_LEVEL = 0x02000000,
        CREATE_SEPARATE_WOW_VDM = 0x00000800,
        CREATE_SHARED_WOW_VDM = 0x00001000,
        CREATE_SUSPENDED = 0x00000004,
        CREATE_UNICODE_ENVIRONMENT = 0x00000400,
        DEBUG_ONLY_THIS_PROCESS = 0x00000002,
        DEBUG_PROCESS = 0x00000001,
        DETACHED_PROCESS = 0x00000008,
        EXTENDED_STARTUPINFO_PRESENT = 0x00080000,
        INHERIT_PARENT_AFFINITY = 0x00010000
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct WTS_SESSION_INFO
    {
        public int SessionID;
        [MarshalAs(UnmanagedType.LPTStr)]
        public string WinStationName;
        public ConnectionState State;
    }

    [DllImport("wtsapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public static extern Int32 WTSEnumerateSessions(IntPtr hServer, int reserved, int version,
                                                    ref IntPtr sessionInfo, ref int count);


    [DllImport("advapi32.dll", EntryPoint = "CreateProcessAsUserW", SetLastError = true, CharSet = CharSet.Auto)]
    static extern bool CreateProcessAsUser(
        IntPtr hToken,
        string lpApplicationName,
        string lpCommandLine,
        IntPtr lpProcessAttributes,
        IntPtr lpThreadAttributes,
        bool bInheritHandles,
        UInt32 dwCreationFlags,
        IntPtr lpEnvironment,
        string lpCurrentDirectory,
        ref STARTUPINFO lpStartupInfo,
        out PROCESS_INFORMATION lpProcessInformation);

    [DllImport("wtsapi32.dll")]
    public static extern void WTSFreeMemory(IntPtr memory);

    [DllImport("kernel32.dll")]
    private static extern UInt32 WTSGetActiveConsoleSessionId();

    [DllImport("wtsapi32.dll", SetLastError = true)]
    static extern int WTSQueryUserToken(UInt32 sessionId, out IntPtr Token);

    [DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public extern static bool DuplicateTokenEx(
        IntPtr hExistingToken,
        uint dwDesiredAccess,
        IntPtr lpTokenAttributes,
        int ImpersonationLevel,
        int TokenType,
        out IntPtr phNewToken);

    private const int TokenImpersonation = 2;
    private const int SecurityIdentification = 1;
    private const int MAXIMUM_ALLOWED = 0x2000000;
    private const int TOKEN_DUPLICATE = 0x2;
    private const int TOKEN_QUERY = 0x00000008;

    /// <summary>
    /// Launches a process for the current logged on user if there are any.
    /// If none, return false as well as in case of 
    /// 
    /// ##### !!! BEWARE !!! ####  ------------------------------------------
    /// This code will only work when running in a windows service (where it is really needed)
    /// so in case you need to test it, it needs to run in the service. Reason
    /// is a security privileg which only services have (SE_??? something, cant remember)!
    /// </summary>
    /// <param name="processExe"></param>
    /// <returns></returns>
    public static bool CreateProcessAsCurrentUser(string processExe)
    {

        IntPtr duplicate = new IntPtr();
        STARTUPINFO info = new STARTUPINFO();
        PROCESS_INFORMATION procInfo = new PROCESS_INFORMATION();

        Debug.WriteLine(string.Format("CreateProcessAsCurrentUser. processExe: " + processExe));

        IntPtr p = GetCurrentUserToken();

        bool result = DuplicateTokenEx(p, MAXIMUM_ALLOWED | TOKEN_QUERY | TOKEN_DUPLICATE, IntPtr.Zero, SecurityIdentification, SecurityIdentification, out duplicate);
        Debug.WriteLine(string.Format("DuplicateTokenEx result: {0}", result));
        Debug.WriteLine(string.Format("duplicate: {0}", duplicate));


        if (result)
        {
            result = CreateProcessAsUser(duplicate, processExe, null,
                IntPtr.Zero, IntPtr.Zero, false, (UInt32)CreateProcessFlags.CREATE_NEW_CONSOLE, IntPtr.Zero, null,
                ref info, out procInfo);
            Debug.WriteLine(string.Format("CreateProcessAsUser result: {0}", result));

        }


        if (p.ToInt32() != 0)
        {
            Marshal.Release(p);
            Debug.WriteLine(string.Format("Released handle p: {0}", p));
        }


        if (duplicate.ToInt32() != 0)
        {
            Marshal.Release(duplicate);
            Debug.WriteLine(string.Format("Released handle duplicate: {0}", duplicate));
        }



        return result;
    }

    public static int GetCurrentSessionId()
    {
        uint sessionId = WTSGetActiveConsoleSessionId();
        Debug.WriteLine(string.Format("sessionId: {0}", sessionId));

        if (sessionId == 0xFFFFFFFF)
            return -1;
        else
            return (int)sessionId;
    }

    public static bool IsUserLoggedOn()
    {
        List<WTS_SESSION_INFO> wtsSessionInfos = ListSessions();
        Debug.WriteLine(string.Format("Number of sessions: {0}", wtsSessionInfos.Count));
        return wtsSessionInfos.Where(x => x.State == ConnectionState.Active).Count() > 0;
    }

    private static IntPtr GetCurrentUserToken()
    {
        List<WTS_SESSION_INFO> wtsSessionInfos = ListSessions();
        int sessionId = wtsSessionInfos.Where(x => x.State == ConnectionState.Active).FirstOrDefault().SessionID;
        //int sessionId = GetCurrentSessionId();

        Debug.WriteLine(string.Format("sessionId: {0}", sessionId));
        if (sessionId == int.MaxValue)
        {
            return IntPtr.Zero;
        }
        else
        {
            IntPtr p = new IntPtr();
            int result = WTSQueryUserToken((UInt32)sessionId, out p);
            Debug.WriteLine(string.Format("WTSQueryUserToken result: {0}", result));
            Debug.WriteLine(string.Format("WTSQueryUserToken p: {0}", p));

            return p;
        }
    }

    public static List<WTS_SESSION_INFO> ListSessions()
    {
        IntPtr server = IntPtr.Zero;
        List<WTS_SESSION_INFO> ret = new List<WTS_SESSION_INFO>();

        try
        {
            IntPtr ppSessionInfo = IntPtr.Zero;

            Int32 count = 0;
            Int32 retval = WTSEnumerateSessions(IntPtr.Zero, 0, 1, ref ppSessionInfo, ref count);
            Int32 dataSize = Marshal.SizeOf(typeof(WTS_SESSION_INFO));

            Int64 current = (int)ppSessionInfo;

            if (retval != 0)
            {
                for (int i = 0; i < count; i++)
                {
                    WTS_SESSION_INFO si = (WTS_SESSION_INFO)Marshal.PtrToStructure((System.IntPtr)current, typeof(WTS_SESSION_INFO));
                    current += dataSize;

                    ret.Add(si);
                }

                WTSFreeMemory(ppSessionInfo);
            }
        }
        catch (Exception exception)
        {
            Debug.WriteLine(exception.ToString());
        }

        return ret;
    }

}

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