C# System.DirectoryServices.AccountManagement Unknown error (0x80005000) UserPrincipal.IsMemberOf()

Question

Similar to the problem in the following MSDN thread: http://social.msdn.microsoft.com/Forums/en-MY/csharplanguage/thread/4c9fea6c-1d0a-4733-a8ac-e3b78d10e999

I am trying to verify whether or not a given user is a member of a group, and our existing functional solutions are too slow (13-16 seconds) and I'm trying to speed it up. I currently have:

public bool IsMemberAD(string userName, string groupName)
{
    var pc = new System.DirectoryServices.AccountManagement.PrincipalContext(System.DirectoryServices.AccountManagement.ContextType.Domain);
    var user = System.DirectoryServices.AccountManagement.UserPrincipal.FindByIdentity(pc, System.DirectoryServices.AccountManagement.IdentityType.SamAccountName,
                                                 userName.ToLower());
    var group = System.DirectoryServices.AccountManagement.GroupPrincipal.FindByIdentity(pc, groupName);

    if (group == null || user == null) return false;

    return user.IsMemberOf(group);    
}

What makes this interesting is that it only returns an error when the user is not in the group directly, but rather a member of a group that is within the target group.

For example:

Steve and Sam are two users, and GroupParent and GroupChild are two groups. Steve and GroupChild are members of GroupParent. Sam is a member of GroupChild. If I call this function on (Steve, GroupParent), it returns true. If I call it on (Sam, GroupParent), I get an error. If I call it on ("fdkjskghkf", GroupParent) it returns false.

I linked an article above with similar issues, but his solution did not work for me, I still got the same error. Ideas?

Answer 1

Thanks to Jon Theriault here the following code fixed this problem for me.

string strName = System.Security.Principal.WindowsIdentity.GetCurrent().Name; // "MW\\dalem"
// This is here because of a .Net error that gets 0x80005000 on "isUser = user.IsMemberOf(groupU);"
string domainName = strName.Split('\\')[0]; 
var pc = new PrincipalContext(ContextType.Domain, domainName);