I've been learning how to NOP functions in C++ or even C but there are very few tutorials online about it. I've been googling for the past few hours now and I'm just stuck. Here is my code.

#include <iostream>
#include <windows.h>
#include <tlhelp32.h>
using namespace std;

//#define NOP 0x90
byte NOP[] = {0x90};

void enableDebugPrivileges() {
    HANDLE hcurrent=GetCurrentProcess();
    HANDLE hToken;
    BOOL bret=OpenProcessToken(hcurrent,40,&hToken);
    LUID luid;
    bret=LookupPrivilegeValue(NULL,"SeDebugPrivilege",&luid);
    TOKEN_PRIVILEGES NewState,PreviousState;
    DWORD ReturnLength;
    NewState.PrivilegeCount =1;
    NewState.Privileges[0].Luid =luid;
    NewState.Privileges[0].Attributes=2;
    AdjustTokenPrivileges(hToken,FALSE,&NewState,28,&PreviousState,&ReturnLength);
}
DWORD GetProcId(char* ProcName)
{
    PROCESSENTRY32   pe32;
    HANDLE         hSnapshot = NULL;

    pe32.dwSize = sizeof( PROCESSENTRY32 );
    hSnapshot = CreateToolhelp32Snapshot( TH32CS_SNAPPROCESS, 0 );

    if( Process32First( hSnapshot, &pe32 ) )
    {
    do{
        if( strcmp( pe32.szExeFile, ProcName ) == 0 )
            break;
    }while( Process32Next( hSnapshot, &pe32 ) );
}

if( hSnapshot != INVALID_HANDLE_VALUE )
    CloseHandle( hSnapshot );

return pe32.th32ProcessID;
}
void WriteMem(DWORD Address, void* Value, size_t Size) {
 DWORD Protect = NULL;

VirtualProtect((LPVOID)Address, 3, PAGE_READWRITE, &Protect); memcpy((void*)Address, Value, 3); VirtualProtect((LPVOID)Address, 3, Protect, &Protect); } void nop_(PVOID address, int bytes){ DWORD d, ds; VirtualProtect(address, bytes, PAGE_EXECUTE_READWRITE, &d); memset(address, 144, bytes); VirtualProtect(address,bytes,d,&ds); }

void MemCopy(HANDLE pHandle, void* Dest, const void* Src, int Len)
{
 DWORD OldProtect;
 DWORD OldProtect2; 
 VirtualProtect(Dest, Len, PAGE_EXECUTE_READWRITE, &OldProtect);
 memcpy(Dest, Src, Len);
 VirtualProtect(Dest, Len, OldProtect, &OldProtect2);
 FlushInstructionCache(pHandle, Dest, Len);
}

int main()
{
   enableDebugPrivileges();

   DWORD pid;
   HANDLE phandle;

   // Obtain the process ID
   pid = GetProcId("gr.exe");
    if(GetLastError())
   {
      cout << "Error_PID_: " << GetLastError() << endl;
      system("pause");
      return -1;
   }

   // Obtain the process handle
   phandle = OpenProcess(PROCESS_ALL_ACCESS,0,pid);
   if(GetLastError())
   {
      cout << "Error_HANDLE_: " << GetLastError() << endl;
      system("pause");
      return -1;
   }

   // Debug info, 0 = bad
   cout <<"pid   : " << pid << endl;
   cout <<"HANDLE: " << phandle << endl << endl;
   system("pause");


   // Change value to
   short iValue   =   -1;
   int choice   =   0;

   BYTE * bGodMode  = (BYTE *) (0x409A7E); // Lives Address


   bool hack = true;
   while(hack)
   {
      system("cls");
      cout << "What hack?\n0. Exit\n1. Lives\n\n!> ";
      cin >> choice;
      switch(choice)
      {
      case 0:
         {
            hack=false;
            break;
         }
      case 1:
         // Modify Time
         cout << "God Mode On\n!> ";
//  cin >> iValue;
//  nop_((PVOID)(0x409A7E), 3);
//   MemCopy(phandle, (PVOID)0x409A7E, &NOP, 1);
   WriteMem((DWORD)(0x00409A7E), (void*)NOP, sizeof NOP);
         if(GetLastError())
         {
            cout << "Error: " << GetLastError() << endl;
            system("pause");
         }
         break;
      default:
         cout << "ERROR!\n";
         break;
      }
      Sleep(100);
   }

   system("pause");
   return 0;
}

This is suppose to NOP the DEC function that is 3 bytes long preventing me from losing lives. However each time I try it, it crashes the hack and says I had a access violation. I tried to look up the reasons and most of them dealt with with the size of the location I'm writing to and what I'm copying from. Otherwise, I have absolutely no idea. Any help would be nice. The game is GunRoar and the base address "0x409A7E" is where the DEC function is.