Cannot read all users from Active Directory - [DirectoryServicesCOMException] MoveNext()

Question

User1829539592 posted

Hello,

my team is using a program written in C# to read all users from a specific OU. The program behaves very strange. Sometimes it is working for a couple of weeks and then without any big changes on our AD or any other related component, it throws an exception. Then it is not working for a couple of weeks and after some time it start to run normally again.

Code

DirectoryEntry searchRoot = new DirectoryEntry("<LDAP string>")

searchRoot.AuthenticationType = AuthenticationTypes.None;
DirectorySearcher search = new DirectorySearcher(searchRoot);

search.Filter = <our filter>;
search.PropertiesToLoad.Add("<some property>");
search.PageSize = 1;

SearchResult result;
SearchResultCollection resultCol = null;

try
{
  resultCol = search.FindAll();
}
catch (Exception ex)
{
  Console.WriteLine(ex.ToString());
}

if (resultCol != null)
{
  Console.WriteLine("Result Count: " + resultCol.Count); //.Count throws the Exception
}

Exception

Unhandled Exception: System.DirectoryServices.DirectoryServicesCOMException: An operations error occurred.

  at System.DirectoryServices.SearchResultCollection.ResultsEnumerator.MoveNext()
  at System.DirectoryServices.SearchResultCollection.get_InnerList()
  at System.DirectoryServices.SearchResultCollection.get_Count()

Additional Information

• I have created a loop to use the MoveNext() function of the enumerator and found out that it loads results up to a specific element and then crashes
• It is always the same element
• After the first exception all retries fail as well
• The program is executed on a domain controller
• The user that starts it is a domain admin (but I have also tried it with an enterprise admin account, so it is probably not a permission issue)

I have come to a point, where I have no more ideas on solving this problem. I would appreciate all your support.

Thanks in advance
Jan

Answer 1

User1829539592 posted

Dear admins,

can you please delete this thread? I couldn't find any button to do it myself. While I was waiting for approval, a Stackoverflow user helped me to find a solution.

Thanks