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POCreateProcessasuser - AccessViolationError
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copied!<p>I am trying to start a Gui tray application from a windows service (LocalSystem) using createProcessasUser - like so:</p> <pre><code> public static System.Diagnostics.Process StartProcessInSession(int sessionID, String commandLine) { IntPtr userToken; if (WTSQueryUserToken(sessionID, out userToken)) { //note that WTSQueryUserToken only works when in context of local system account with SE_TCB_NAME IntPtr lpEnvironment; if (CreateEnvironmentBlock(out lpEnvironment, userToken, false)) { StartupInfo si = new StartupInfo(); si.cb = Marshal.SizeOf(si); si.lpDesktop = "winsta0\\default"; si.dwFlags = STARTF.STARTF_USESHOWWINDOW; si.wShowWindow = ShowWindow.SW_SHOW; ProcessInformation pi; if (CreateProcessAsUser(userToken, null, new StringBuilder(commandLine), IntPtr.Zero, IntPtr.Zero, false, CreationFlags.CREATE_NEW_CONSOLE | CreationFlags.CREATE_UNICODE_ENVIRONMENT, lpEnvironment, null, ref si, out pi)) { CloseHandle(pi.hThread); CloseHandle(pi.hProcess); //context.Undo(); try { return System.Diagnostics.Process.GetProcessById(pi.dwProcessId); } catch (ArgumentException e) { //The process ID couldn't be found - which is what always happens because it has closed return null; } } else { int err = Marshal.GetLastWin32Error(); throw new System.ComponentModel.Win32Exception(err, "Could not create process.\nWin32 error: " + err.ToString()); } } else { int err = Marshal.GetLastWin32Error(); throw new System.ComponentModel.Win32Exception(err, "Could not create environment block.\nWin32 error: " + err.ToString()); } } else { int err = System.Runtime.InteropServices.Marshal.GetLastWin32Error(); if (err == 1008) return null; //There is no token throw new System.ComponentModel.Win32Exception(err, "Could not get the user token from session " + sessionID.ToString() + " - Error: " + err.ToString()); } } </code></pre> <p>I am using the function as so:</p> <pre><code> protected override void OnStart(string[] args) { _agentProcess = StartProcessInSession(WTSGetActiveConsoleSessionId(), "Some_correct_path"); } </code></pre> <p>This actually worked for a little while, but in one of my runs it suddenly stopped working... giving the following error when executing the CreateProccessAsUser command (cant go any deeper)</p> <pre><code>{"Attempted to read or write protected memory. This is often an indication that other memory is corrupt."} </code></pre> <p>I have no idea why this is happening or even how to debug this any further, anyhow has any idea?? because this doesnt make any sense to me.</p> <p>CreateProccessasuser definition:</p> <pre><code>[DllImport("advapi32.dll", SetLastError = true, CharSet = CharSet.Auto)] static extern bool CreateProcessAsUser(IntPtr hToken, String lpApplicationName, [In] StringBuilder lpCommandLine, IntPtr /*to a SecurityAttributes struct or null*/ lpProcessAttributes, IntPtr /*to a SecurityAttributes struct or null*/ lpThreadAttributes, bool bInheritHandles, CreationFlags creationFlags, IntPtr lpEnvironment, String lpCurrentDirectory, ref StartupInfo lpStartupInfo, out ProcessInformation lpProcessInformation); </code></pre> <p>Thanks</p>

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