How to change password in AD using C#?

See more:

C#

Windows

Hello

I would like to change a user's passwort in AD using C#. The user has been found (my computer) but throws exception (password policy) while trying to change the password - we chose a password that meets the password policy requirements. On my friends computer the user couldn't be found. We don't know what's wrong - the user exists on both computers (lokal user).

We searched for a long time on the internet but didn't find any solution for our problem.

We appreciate every help. Thank you.

What I have tried:

I tried following code:

String domain = configurationProvider.Configuration.DomainName;
ContextType contextType = ContextType.Machine;
        
public int newPassword(string username, string oldPassword, string newPassword)
  using (PrincipalContext pc = new PrincipalContext(contextType, domain))
  {
    using (UserPrincipal userPrincipal = UserPrincipal.FindByIdentity(pc, username))
    {
      if (userPrincipal != null)
      {
        try { userPrincipal.ChangePassword(oldPassword, newPassword); }
        catch (PasswordException pe) { return null; }
      }
    }
  }
}