Active Directory Group Members Issue

I am using the below code to get the members from a group.

private static List<string> GetGroupMembers(string groupName)
{
  Tracer.LogEntrace(groupName);

  List<string> retVal = new List<string>();

  GroupPrincipal groupPrincipal = 
    GroupPrincipal.FindByIdentity(
      new PrincipalContext(ContextType.Domain), 
      IdentityType.SamAccoun开发者_如何学PythontName,
      groupName);

  PrincipalSearchResult<Principal> principleSearchResult = 
    groupPrincipal.GetMembers(true);

  if (principleSearchResult != null)
  {
     try
     {
        foreach (Principal item in principleSearchResult)
           retVal.Add(item.DistinguishedName);
     }
     catch (Exception ex)
     {
        Tracer.Log(ex.Message);
     }
  }
  else
  {
    //Do Nothing
  }

  Tracer.LogExit(retVal.Count);

  return retVal;

}

It works well for all groups but when its come to the Users group I am getting the error below

"An error (87) occurred while enumerating the groups. The group's SID could not be resolved."

Users in Active Directory is not a group - it's a container. That's why you can't enumerate it like a group - you'll have to enumerate it like an OU (Organizational Unit).

Something like:

// bind to the "Users" container
DirectoryEntry deUsers = new DirectoryEntry("LDAP://CN=Users,DC=yourcompany,DC=com");

// enumerate over its child entries
foreach(DirectoryEntry deChild in deUsers.Children)
{
   // do whatever you need to do to those entries
}