I can't reset Active Directory user password by the admin using C# .NET Core 6

Question

I'm Trying to reset active directory user password by .NET core web API but always return below exception, even if I put very complex password

System.DirectoryServices.AccountManagement.PasswordException: 'The password does not meet the password policy requirements. Check the minimum password length, password complexity and password history requirements. (0x800708C5)'

I tried both ways (DirectoryEntry and the new one) but I get the same exception.

Here is my code, but I think

public bool ResetPassword(string oldPassword, string newPassword, string userNameI)
{
    /*  // set up domain context
    PrincipalContext context = new PrincipalContext(ContextType.Domain, LDAP_PATH, userName, password);

    if (context != null)
    {
        // find the user you want to delete
        UserPrincipal user = UserPrincipal.FindByIdentity(context, IdentityType.SamAccountName, userNameI);

        if (user != null)
        {
            user.Enabled = true;
            user.ChangePassword(oldPassword,newPassword);
            user.ExpirePasswordNow();
            user.Save();

            return true;
        }
    }*/

    /*  
    var entry = new DirectoryEntry
                    {
                        Path = "LDAP://MyIP",
                        Username = userName,
                        Password = password
                    };

    using (var searcher = new DirectorySearcher(entry))
    {
        searcher.Filter = "(SAMAccountName=" + userNameI + ")";

        var result = searcher.FindOne();

        var user = result.GetDirectoryEntry();

        user.Invoke("ChangePassword", new object[] { oldPassword.Trim(), newPassword.Trim() });
        user.CommitChanges();

        return true;
    }
    */

    using (PrincipalContext ctx = new PrincipalContext(ContextType.Domain, "LDAPIP", userName, password))
    {
        using (UserPrincipal user = UserPrincipal.FindByIdentity(ctx, IdentityType.SamAccountName, userNameI))
        {
            if (user != null)
            {
                user.ChangePassword(oldPassword, newPassword);
                user.Save();

                return true;
            }
            else
            {
                throw new Exception(string.Format("Username not found: {0}", userNameI));
            }
        }

        return false;
    }
}

Answer 1

The below code is working fine, the Old password is not needed in resetting password and account owner user name is needed :

        public bool ResetPassword(string newPassword, string accountOwneruserName /*user name for the user that you want to change his password*/)
        {

            using (PrincipalContext ctx = new PrincipalContext(ContextType.Domain, "17x.xx.xx.x" /*Active Directory server Ip*/, adminUserName, adminPassword ))
            {
                using (UserPrincipal user = UserPrincipal.FindByIdentity(ctx, IdentityType.SamAccountName, accountOwneruserName))
                {

                    if (user != null)
                    {
                  
                        user.SetPassword(newPassword.Trim());
                        user.Save();
                        return true;
                    }
                    else
                    {
                        throw new Exception(string.Format("Username not found: {0}", accountOwneruserName));
                    }
                }
                return false;
            }

        }