Hello everyone. I am hoping someone could tell me the problem with this code. This code works on Windows200 Professional but does not work on WindowsNT 4.0. I am using VisualC++ 6.0 with a windows api project and passing in a path in the program arguments inside of projects->settings debug tab. Now my code worked on both Windows2k Pro and windowsNT 4.0 yesterday, this was the code yesterday WndClass.cbSize = sizeof(WNDCLASSEX); WndClass.style = NULL; WndClass.lpfnWndProc = WindowFunc; WndClass.cbClsExtra = 0; WndClass.cbWndExtra = 0; WndClass.hInstance = hInstance; WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION); WndClass.hCursor = LoadCursor(NULL, IDC_ARROW); WndClass.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); WndClass.lpszMenuName = NULL; WndClass.lpszClassName = "test"; WndClass.hIconSm = LoadIcon(NULL, IDI_APPLICATION); if(!RegisterClassEx(&WndClass)) { MessageBox(0, "Window Registration Failed!", "Error!", MB_ICONEXCLAMATION | MB_OK | MB_SYSTEMMODAL); return 0; } hwnd = CreateWindowEx( WS_EX_CLIENTEDGE, "test", "Rimage CD Feeder", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 320, 240, NULL, NULL, hInstance, NULL); if(hwnd == NULL) { MessageBox(0, "Window Creation Failed!", "Error!", MB_ICONEXCLAMATION | MB_OK | MB_SYSTEMMODAL); return 0; } ShowWindow(hwnd, SW_MINIMIZE); UpdateWindow(hwnd); PostMessage(hwnd, WM_COMMAND, (WPARAM)NULL, (LPARAM)NULL); As I said this worked on both Win2k and WindowsNT 4.0 yesterday and I changed the code to look like this... if(strlen(lpszArgs)) { strcpy(INIFileName, lpszArgs); } else { GetModuleFileName(hInstance, INIFileName, MAX_PATH); ptrFilePosition = strrchr(INIFileName, ''.''); *(++ptrFilePosition) = NULL; strcat(INIFileName, "ini"); } WndClass.cbSize = sizeof(WNDCLASSEX); WndClass.style = NULL; WndClass.lpfnWndProc = WindowFunc; WndClass.cbClsExtra = 0; WndClass.cbWndExtra = 0; WndClass.hInstance = hInstance; WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION); WndClass.hCursor = LoadCursor(NULL, IDC_ARROW); WndClass.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); WndClass.lpszMenuName = NULL; WndClass.lpszClassName = "test"; WndClass.hIconSm = LoadIcon(NULL, IDI_APPLICATION); if(!RegisterClassEx(&WndClass)) { MessageBox(0, "Window Registration Failed!", "Error!", MB_ICONEXCLAMATION | MB_OK | MB_SYSTEMMODAL); return 0; } hwnd = CreateWindowEx( WS_EX_CLIENTEDGE, "test", "Rimage CD Feeder", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 320, 240, NULL, NULL, hInstance, NULL); if(hwnd == NULL) { MessageBox(0, "Window Creation Failed!", "Error!", MB_ICONEXCLAMATION | MB_OK | MB_SYSTEMMODAL); return 0; } ShowWindow(hwnd, SW_MINIMIZE); UpdateWindow(hwnd); PostMessage(hwnd, WM_COMMAND, (WPARAM)NULL, (LPARAM)NULL); where lpszArgs is the 3rd param from WinMain. I also modified another function including adding a new param to the function which gets called later in the program, which should have nothen to do with this problem i would think? Now When I run this code she works fine on both WindowsNT 4.o and Win2k Pro until I get to this part of the code : hwnd = CreateWindowEx( WS_EX_CLIENTEDGE, "test", "Rimage CD Feeder", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 320, 240, NULL, NULL, hInstance, NULL); When I get to this code she just ENDS with the message "The thread 0x36 has exited with code 1 (0x1)." and The program has exited with code 1 (0x1). Now when I run this on Windows2k it works fine, it creates the window and able to step through the rest of my program. I can''t figure out what could be wrong? I have tried this code on 1 windows2k pro machine which it works fine and 2 different WinNT 4.0 machines which it don''t work at all. Can someone tell me why i''m having this problem? Thanks in advance. Braves