Directory Programming .NET

Hi All,
I have a webpage project that can create user in Active directory.
It works fine with active directory 2003. But on Active Directory 2008 I can not create account through my webpage. It alsway show "access denied". Here is my code:
 using (Aladin.Security.RevertToAppPool.Revert())
            {
                using (Aladin.Security.ScopeImpersonator imp = new Aladin.Security.ScopeImpersonator(this.administrativeLoginName, this.domainName, administrativePassword))
                {
                                using (DirectoryEntry user = ouEntry.Children.Add("CN=" + this.displayName, "user"))
                                {
                                    this.SetDirectoryEntryProperty(user, "mail", email);

                                    this.SetDirectoryEntryProperty(user, "UserPrincipalName", this.userName);
                                    this.SetDirectoryEntryProperty(user, "sAMAccountName", this.userName);
                                    this.SetDirectoryEntryProperty(user, "userAccountControl", ((int)UserStatus.Enable).ToString());
                                    user.CommitChanges();
                                  
                                }
                }
            }
private void SetDirectoryEntryProperty(DirectoryEntry entry, string attribute, string value)
        {
            if (entry.Properties.Contains(attribute))
            {
                entry.Properties[attribute][0] = value;
            }
            else
            {
                entry.Properties[attribute].Add(value);
            }
        }

These above code run well if I use Administrator account. But it show message acess denied if I use other account which have the same permission with Administrator.

Can you have me to solve this issue.
Thanks,
Aladin

The best way to troubleshoot this is to access the ouEntry.Properties["allowedChildClassesEffective"] attribute (you may need to load it via RefreshCache first) to see if both users that you attempt to log in with actually do have "user" listed as one of the values in the returned array. This will tell you if you really have the permissions that you think you have.

Thank You very much for your help.
I have solved my problem.