NetUserChangePassword C++

Question

I would like to change user password on my Windows 7 PC using C++.

But when I compile it gets error:

 undefined reference to 'NetUserChangePassword' 
 [Error] ld returned 1 exit status.`

How can I fix it?

Here is the MSDN page with the NetUserChangePassword function:

#ifndef UNICODE
    #define UNICODE
#endif
#pragma comment(lib, "netapi32.lib")
#include <iostream>
#include <stdio.h>
#include <windows.h>
#include <lm.h>

bool ChangeUserPassword(LPCWSTR OldPassword, LPCWSTR NewPassword)
{
    NET_API_STATUS nStatus;
    LPTSTR lp = new TCHAR[256];
    DWORD dw = 256;
    GetUserName(lp, &dw);
    nStatus = NetUserChangePassword(NULL, lp, OldPassword, NewPassword);
    delete[] lp;
    if (nStatus == NERR_Success)
        return true;
    return false;
}

int main(int argc, char** argv)
{
    LPCWSTR Old_P = L"C";
    LPCWSTR New_P = L"D";
    ChangeUserPassword(Old_P, New_P);
    return 0;
}

I tried to link to the project the winapi32.dll in two ways

i tried to add using the project option

i tried to add following line

HINSTANCE hInst = LoadLibrary( L"C:\\Windows\\System32\\netapi32.dll ");

but i get always the same error

possible duplicate of [What is an undefined reference/unresolved external symbol error and how do I fix it?](http://stackoverflow.com/questions/12573816/what-is-an-undefined-reference-unresolved-external-symbol-error-and-how-do-i-fix) — πάντα ῥεῖ, Apr 12 '14 at 21:30
ensure that the path to the Lib folder of your SDK installation is part of the library search pathes of your linker project settings — 4pie0, Apr 12 '14 at 21:32

David Heffernan · Accepted Answer · 2014-04-13T16:45:59.520

1

The requirements section of the MSDN topic you linked to states that you must link the Netapi32.lib library. That is the step that you have missed and explains the missing external error.

As to how to resolve the problem it is hard to say for sure. You are not using the MS compiler and so the #pragma approach won't work. Consult the docs for your compiler/linker to work out how to link this library.

It looks like you are using a GCC based compiler and so need to add -lnetapi32 to the options.

edited Apr 13 '14 at 16:45

answered Apr 12 '14 at 21:37

David Heffernan

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this line doesn't link NetApi32.lib ? #pragma comment(lib, "netapi32.lib") – Michele Apr 12 '14 at 21:43
Not in your compiler. Use -l to specify libraries. – David Heffernan Apr 12 '14 at 21:49
I'm not sure why you unaccepted. This is surely the answer. – David Heffernan Apr 13 '14 at 16:28
You cannot expect any more specific instructions. You did not tell us the compiler that you use. You need to pass that library to your linker. What did the documentation for your compiler say? Did you read it like I suggested? – David Heffernan Apr 13 '14 at 16:39
i wrote but the answer was cancelled sorry – Michele Apr 13 '14 at 16:40
i use DevCpp v 5.4.2. – Michele Apr 13 '14 at 16:40
that was not part of the question that I answered. Did you read the docs? – David Heffernan Apr 13 '14 at 16:41
Yes but i have to link to project Netapi32.dll ? – Michele Apr 13 '14 at 16:47
You have to pass netapi32.lib to the linker. That's it. Did you read the docs? – David Heffernan Apr 13 '14 at 16:48
Docs doesn't help a lot – Michele Apr 13 '14 at 16:56
I guess you also need to learn a bit about how linking works because your knowledge is hazy. – David Heffernan Apr 13 '14 at 16:57

NetUserChangePassword C++

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