这是源代码的副本：
extrn MessageBoxA: PROC
extrn ExitProcess: PROC
.data
mytit db 'The 64-bit world of Windows & assembler...', 0
mymsg db 'Hello World!', 0
.code
main proc
mov r9d, 0 ; uType = MB_OK
lea r8, mytit ; LPCSTR lpCaption
lea rdx, mymsg ; LPCSTR lpText
mov rcx, 0 ; hWnd = HWND_DESKTOP
call MessageBoxA
mov ecx, eax ; uExitCode = MessageBox(...)
call ExitProcess
main endp
End
现在，我只是想让我的“第一个”x64 汇编程序启动并运行，这样我就可以开始玩耍并实际学习一些汇编，所以我只是从这里复制了这个源代码，试图看看我是否能得到任何可以正确组装的东西，但到目前为止，还没有运气。
如果我组装它，我不会得到任何错误，无论是在组装时还是运行时，但程序没有按预期运行：它似乎根本没有做任何事情。一旦生成了可执行文件并双击它，什么也没有发生，如果我转到任务管理器，它似乎也没有在后台运行。这是怎么回事？
我正在使用 MASM64 的默认设置，这些设置是在检查“构建自定义...”下的“masm”时生成的（通过右键单击解决方案资源管理器中的项目来找到）并在配置管理器中将平台从 Win32 更改为 x64，例外情况是我已将“入口点”链接器选项更改为“main”，将“子系统”链接器选项更改为“Windows”。（所有这些都在 Visual Studio 2012 中完成。）
在 Visual Studio 中运行程序生成的调试信息是
'Hello World (ASM).exe' (Win32): Loaded 'D:\Google Drive\My Documents\Visual Studio
2012\Projects\Hello World (ASM)\x64\Release\Hello World (ASM).exe'. Symbols loaded.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\ntdll.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\kernel32.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\KernelBase.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\user32.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\gdi32.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\imm32.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\msctf.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\msvcrt.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\nvinitx.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\advapi32.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\sechost.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\rpcrt4.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Program Files\NVIDIA Corporation\coprocmanager\detoured.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Program Files\NVIDIA Corporation\coprocmanager\Nvd3d9wrapx.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\setupapi.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\cfgmgr32.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\devobj.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Program Files\NVIDIA Corporation\coprocmanager\nvdxgiwrapx.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\PROGRA~1\NVIDIA~1\NVSTRE~1\rxinput.dll'. Module was built without symbols.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\ole32.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\oleaut32.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Loaded 'C:\Windows\System32\combase.dll'. Cannot find or open the PDB file.
'Hello World (ASM).exe' (Win32): Unloaded 'C:\PROGRA~1\NVIDIA~1\NVSTRE~1\rxinput.dll'
'Hello World (ASM).exe' (Win32): Unloaded 'C:\Windows\System32\combase.dll'
'Hello World (ASM).exe' (Win32): Unloaded 'C:\Windows\System32\oleaut32.dll'
'Hello World (ASM).exe' (Win32): Unloaded 'C:\Windows\System32\ole32.dll'
First-chance exception at 0x000007FA9A09B9FB (gdi32.dll) in Hello World (ASM).exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.
Unhandled exception at 0x000007FA9A09B9FB (gdi32.dll) in Hello World (ASM).exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.
First-chance exception at 0x000007FA9A09B9FB (gdi32.dll) in Hello World (ASM).exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.
Unhandled exception at 0x000007FA9A09B9FB (gdi32.dll) in Hello World (ASM).exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.
First-chance exception at 0x000007FA9A09B9FB (gdi32.dll) in Hello World (ASM).exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.
Unhandled exception at 0x000007FA9A09B9FB (gdi32.dll) in Hello World (ASM).exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.
The program '[1080] Hello World (ASM).exe' has exited with code 0 (0x0).