В чем причина ошибки при получении адреса функции из dll с помощью функции GetProcAddress?

#include<windows.h>
HHOOK _hook;
int code;
bool key;
UINT scancode;
WPARAM wPararam;
LRESULT CALLBACK KeyProc(int ncode,WPARAM wParam,LPARAM lParam){
    KBDLLHOOKSTRUCT * pStruct = (KBDLLHOOKSTRUCT *)lParam;
    code=pStruct->vkCode;scancode=pStruct->scanCode;
    wPararam=wParam;
    if(wParam==WM_KEYUP){key=false;code=0;}else{key=true;}
    return CallNextHookEx(_hook,ncode,wParam,lParam);
}

#include<windows.h>
#include<iostream>
#include"hook.h"
using namespace std;
int main(){
int (*func)();
FUNC func;
MSG msg;
HINSTANCE hinstDLL;
hinstDLL=LoadLibrary("dll.dll");
 (FARPROC &)func=GetProcAddress(hinstDLL,"KeyProc");
_hook = SetWindowsHookEx(WH_KEYBOARD,0,hinstDLL,func);
while(1){
PeekMessage(&msg,NULL,0,0,0);   
}
    }

_hook=SetWindowsHookEx(WH_KEYBOARD,func,hinstDLL,0);

#include<windows.h>
#include<iostream>
#include"hook.h"
using namespace std;
int main(){
HOOKPROC func;
typedef FARPROC(*FUNC)();
FUNC func2;
MSG msg;
HINSTANCE hinstDLL;
hinstDLL=LoadLibrary("dll.dll");
func=(HOOKPROC)GetProcAddress(hinstDLL,"_Z7KeyProcijl@12");
func2=(FUNC)GetProcAddress(hinstDLL,"_Z7num_keyv");
SetWindowsHookEx(WH_KEYBOARD,func,hinstDLL,0);
while(1){
    if((int)func2()!=0)
    cout<<(int)func2();
PeekMessage(&msg,NULL,0,0,0);
}
}

#include<windows.h>
HHOOK _hook;
int code=0;
LRESULT CALLBACK KeyProc(int ncode,WPARAM wParam,LPARAM lParam){
    code=(int)wParam;
    MessageBox(NULL,"123","hook!",MB_ICONWARNING);
    return CallNextHookEx(_hook,ncode,wParam,lParam);
}
int num_key(){
    return code;
}