C#:Active Directory:Check/Uncheck User must change password at next logon

        public void SetuserHasToChangePasswordsInTheNextLoginProperty(bool userHasToChangePasswordsInTheNextLogin)
        {
            DirectoryEntry de = GetDirectoryObject(UserName);
            if (userHasToChangePasswordsInTheNextLogin)
            {
                ActiveDirectoryHelper.SetProperty(de, "pwdLastSet", 0);
            }
            else
            {
                ActiveDirectoryHelper.SetProperty(de, "pwdLastSet", -1);
            }
            de.CommitChanges();
        }

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