CODEWITHSUNDEEP
c++memory-address
d0n.key
d0n.key

Reputation: 1483

WriteProcessMemory() returns 487? Value found using CheatEngine

As written up there (^), I've got a problem with C++ and WriteProcessMemory(). I opened the Windows- Calc.exe, stored a number with and opened CheatEngine. I found the number (changed it e.t.c.) and put it in this program: (Note: I'm german; "Rechner" is equal to "Calculator")

#include <iostream>
#include <Windows.h>
using namespace std;

int main (){
    int Value = 500;
    HWND hWnd = FindWindow(0, L"Rechner");

    if (!hWnd) {
        cerr << "Can't find window" << endl;
        return 0;
        }

    DWORD PID;
    GetWindowThreadProcessId(hWnd, &PID);
    HANDLE hProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, PID);

    if (!hProcess) {
        cerr << "Process handle error" << endl;
        return 0;
        }
    int iSuccess = WriteProcessMemory(hProcess, (LPVOID)0x899FC6F60C , &Value, (DWORD)sizeof(Value), NULL);
    int i = 0;
    while (iSuccess == 0){
        i = i+1;
        cerr << "Failed " << i  << "  Error:   " << GetLastError() << endl;
        iSuccess = WriteProcessMemory(hProcess, (LPVOID)0x899FC6F60C , &Value, (DWORD)sizeof(Value), NULL);  //Here all begins
        }
    clog << "Done" << endl;
    CloseHandle(hProcess);
    return 0;
}

Window got found, Process got found (No errors there..) But then, the "//Here all begins" line returns 0, and sets GetLastError() to 487. Like all of the followings. If you know, what I've done wrong, please describe it noob-friendly, I began C++ yesterday.

Upvotes: 0

Views: 1087

Answers (1)

Christopher
Christopher

Reputation: 8992

See this link for a description of what the GetLastError codes mean.

In this case ERROR_INVALID_ADDRESS, Attempt to access invalid address.

This is due to the fact, that you are writing to a 'random' memory address. You cannot just take a number and hope that there will be memory in the other process at this address.

Upvotes: 1

Related Questions