刚学win32汇编，写了个汇编程序，报了好多错，该如何解决

源文件
想使用debug中的PintHex来输出最终三数相加的结果

; AddVariables.asm
.386
.model flat, stdcall
.stack 4096
ExitProcess PROTO, dwExitCode:DWORD


include \masm32\include\windows.inc
include \masm32\include\kernel32.inc
include \masm32\include\masm32.inc
include \masm32\include\debug.inc 

includelib \masm32\lib\masm32.lib
includelib \masm32\lib\kernel32.lib
includelib \masm32\lib\debug.lib

.data 
firstval DWORD 20002000h
secondval DWORD 11111111h
thirdval DWORD 22222222h
sum DWORD 0

PrintHex sum, "Sum value"

.code
main PROC
    mov eax, firstval
    add eax, secondval
    add eax, thirdval
    mov sum, eax

    INVOKE ExitProcess,0
main ENDP
END main

使用如下命令进行汇编
ml /c /coff AddVariabes.asm
报错信息

option casemap:none