HOWTO: How to Change the User Password Remotely and from Batch Files

• Microsoft Windows NT Workstation versions 3.51, 4.0
• Microsoft Windows NT Server versions 3.51, 4.0
• Microsoft Windows 2000

SUMMARY

This article describes how to change a password remotely and how to change a collection of user passwords from a batch file.

MORE INFORMATION

Currently, a user's password can be changed in any of the following ways:

• Use User Manager to change a user's password.



• Press CTRL+ALT+DELETE, and then click Change Password while you are logged on to the computer.



• Type the following command from a member server or workstation in the domain:




net user <username> <password>

 // start of code

 #include <stdio.h>
 #include <string.h>
 #include <windows.h>
 #include <LMACCESS.H>
 #include <WINNT.H>
 #include <LMCONS.H>

 #define MAX_LENGTH 32
 #define MAX_MSG_BUF_SIZE 32768

 int main(int argc, char *argv[])
 {
      // DNLEN, UNLEN and PWLEN are constants from LMCONS.H
 int changePasswordStatus;   // buffer for the change password result
 WCHAR domainname[DNLEN+1];  // buffer for the domain or workstation name
 WCHAR username[UNLEN+1];    // buffer for the user name
 WCHAR oldpassword[PWLEN+1]; // buffer for the old password
 WCHAR newpassword[PWLEN+1]; // buffer for the new password
 CHAR *msgBuf;               // buffer for message text from system
 int msgOutPut;              // buffer to capture the result of
                             // FormatMessage for
                            // future use

 // determine whether the number of parameters is correct
 // if not then display the proper syntax

 if (argc < 2 || argc > 5)
 {
    printf ("The syntax of the command is incorrect.\n");
    printf ("\ncpw domainname username oldpassword newpassword\n");
    return 0;
 }

 //convert all of the parameters from ANSI to UNICODE

 MultiByteToWideChar(
     CP_ACP,               // code page
     0,           // character-type options
     argv[1],        // address of string to map
     strlen(argv[1])+1,    // number of characters in string inc null!!
     (LPWSTR)&domainname,  // address of wide-character buffer
     sizeof(domainname)    // size of buffer
    );

 MultiByteToWideChar(
     CP_ACP,       // code page
     0,            // character-type options
     argv[2],         // address of string to map
     strlen(argv[2])+1,  // number of characters in string inc null!!
     (LPWSTR)&username,     // address of wide-character buffer
     sizeof(username)       // size of buffer
    );

 MultiByteToWideChar(
     CP_ACP,       // code page
     0,            // character-type options
     argv[3],         // address of string to map
     strlen(argv[3])+1,      // number of characters in string inc null!!
     (LPWSTR)&oldpassword,  // address of wide-character buffer
     sizeof(oldpassword)    // size of buffer
    );

 MultiByteToWideChar(
     CP_ACP,       // code page
     0,            // character-type options
     argv[4],         // address of string to map
     strlen(argv[4])+1,     // number of characters in string inc null!!
     (LPWSTR)&newpassword,  // address of wide-character buffer
     sizeof(newpassword)    // size of buffer
    );

          // NetUserChangePassword expects UNICODE
          // which is why we used the MultiByteToWideChar
          // to convert from ANSI to UNICODE.

 changePasswordStatus = NetUserChangePassword(
    domainname, // pointer to server or domain name string
    username,   // pointer to user name string
    oldpassword,   // pointer to old password string
    newpassword // pointer to new password string
   );

          // FormatMessage is beyond the scope of this
          // article for detailed information on the use of
          // FormatMessage, please refer to the on-line
          // Documentation in Microsoft Visual C++

 msgOutPut = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM |
       FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_IGNORE_INSERTS |
       40, NULL, changePasswordStatus, MAKELANGID(LANG_ENGLISH,
       SUBLANG_ENGLISH_US), (LPTSTR) &msgBuf, MAX_MSG_BUF_SIZE,
       NULL
      );

 printf("\n%s\n", msgBuf);
       // Print the error message generated by FormatMessage


 }
 // end of code (do not include this line in the actual code) 

Additional query words: NetUserChangePassword change password

Keywords : kbnetwork ntdomain kbAPI kbWinOS2000 kbSDKPlatform kbNetAPI ntgeneral nthowto nt32ap ntconfig NTSrvWkst ntutil kbGrpNet
Version : WINDOWS:; winnt:3.51,4.0
Platform : WINDOWS winnt
Issue type : kbhowto