Question

I can query for users with the following, but I would like to add an additional OU=Good to the search DN. Is this possible without hard coding the full path to the GC?

Forest myForest = Forest.GetCurrentForest();
GlobalCatalog cat = myForest.FindGlobalCatalog();
DirectorySearcher srch = cat.GetDirectorySearcher();
srch.Filter = "(&(objectClass=user)(samaccountname=myuser))";
SearchResult result = srch.FindOne();

Answer 1

You might try to get the DirectoryEntry for your global catalog, and then search its .Children property for the OU you’re looking for, and then use that DirectoryEntry as your search root – something like (untested, don’t have AD at hand to test):

Forest myForest = Forest.GetCurrentForest();
GlobalCatalog cat = myForest.FindGlobalCatalog();

DirectoryEntry deGlobal = cat.GetDirectoryEntry();

DirectoryEntry deYourOU = deGlobal.Children.Find("OU=Good");

DirectorySearcher srch = new DirectorySearcher(deYourOU);

Of course, in reality, you’d want to add some error checking ( != null and so on) to your code – but that would be the basic way of getting at your OU (I hope!)