Reading/Writing ADAM users' attributes

I am new to ADAM and Active Directory and was wondering if someone can give
me a little guidance. I am using VS.Net 2008, C#, and .Net Framework 3.5
SP1. I would like to read/write to/from users' attributes in ADAM. My ADAM
instance is secured with a certificate and I can connect and call it just
fine using System.Web.Security.Membership. The problem is that Membership
does not expose all the attributes and I need to be able to read/write to
them. So, I need to be implement my own thing to do so.

I have a sample code below to try to read an attribute. I keep getting
"System.Runtime.InteropServices.COMException: The server is not operational."
error. Does anyone know why I'm getting this?

DirectoryEntry user = new DirectoryEntry(
"LDAP://{hostname}:{secured port}/o={organization},cn={users
container},dc={domain},dc=COM",
{ADAM admin user},
{ADAM admin password},
AuthenticationTypes.Secure
);


string path = user.Path;
AdsUserFlags userFlags =
(AdsUserFlags)user.Properties["userAccountControl"].Value;

Where: AdsUserFlags is an enumeration mapped to AD user flags.

Your help is greatly appreciated!