CreateProcess() fails with an access violation [duplicate]

The second argument is a LPTSTR, namely a pointer to a non-const char array. The docs specifically say:

this parameter cannot be a pointer to read-only memory (such as a const variable or a literal string)

The reason passing a string literal is a problem:

The system adds a terminating null character to the command-line string to separate the file name from the arguments. This divides the original string into two strings for internal processing.

Which means in your case, it tries to modify read-only memory, hence the crash.

Try this, it should work.

TCHAR lpszClientPath[500]= TEXT("c:\\users\\e\\desktop\\mspaint.exe");if(!CreateProcess(NULL, lpszClientPath, NULL, NULL, FALSE,  NORMAL_PRIORITY_CLASS|CREATE_NEW_CONSOLE|CREATE_UNICODE_ENVIRONMENT,NULL, NULL, &si, &pi))            {    printf( "CreateProcess failed (%d).\n", GetLastError() );        return;            }......

Change you code to this:

#include <windows.h>#include <stdio.h>#include <tchar.h>void _tmain( int argc, TCHAR *argv[] ){    TCHAR ProcessName[256];    STARTUPINFO si;    PROCESS_INFORMATION pi;    wcscpy(ProcessName,L"c:\\users\\e\\desktop\\mspaint.exe");    ZeroMemory( &si, sizeof(si) );    si.cb = sizeof(si);    ZeroMemory( &pi, sizeof(pi) );    /*    if( argc != 2 )    {        printf("Usage: %s [cmdline]\n", argv[0]);        return;    }    */    // Start the child process.     if( !CreateProcess( NULL,   // No module name (use command line)        ProcessName,        // Command line        NULL,           // Process handle not inheritable        NULL,           // Thread handle not inheritable        FALSE,          // Set handle inheritance to FALSE        0,              // No creation flags        NULL,           // Use parent's environment block        NULL,           // Use parent's starting directory         &si,            // Pointer to STARTUPINFO structure        &pi )           // Pointer to PROCESS_INFORMATION structure    )     {        printf( "CreateProcess failed (%d).\n", GetLastError() );        return;    }    // Wait until child process exits.    WaitForSingleObject( pi.hProcess, INFINITE );    // Close process and thread handles.     CloseHandle( pi.hProcess );    CloseHandle( pi.hThread );}