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Strict Extern "win32" Function MessageBoxW( hwnd, lpText$w, lpCaption$w, uType ) EndExtern MessageBoxW( Null, "Message body text!", "Titlebar Text", 0 )When accessing the Windows API in BlitzMax, you may as well use the unicode (wide-character) implementations of the functions which have a 'W' suffix instead of 'A' unless you are planning on running your programs on Windows 9X/Me.