The server is not operational while accessing active directory

[Sanky]

Hi All,
Urgent help required. I am able to access active directory through
remote machine.

This code works fine if i run it on the server that contains a active
directory and i have
all installed .net on it as its a test environment.

string path =
"LDAP://otis-mlsserver.MyDomain.com/DC=MyDomain,DC=COM";
DirectoryEntry entry = new DirectoryEntry(
path, "otis-mlsserver.MyDomain.com\\administrator",
"Rocky1996");

try
{
// Bind to the native object to force authentication to
happen
Object native = entry.NativeObject;
MessageBox.Show("Done");
}
catch (Exception ex)
{
//throw new Exception("User not authenticated: " +
ex.Message);
MessageBox.Show(ex.Message);
}


But when i try to run the same code in a client machine i get a error
"Server is not operational".Since its a test environment i am not
logging to the server that contains
the domain.I mean that when i want to test this application i change my
IP setting and
out my current machine on the network hub which also contains the
server.Then i am able to ping the server.But i dont login to the domain
of the server.But i put the DNS entry of the server in my client
machine.

Can any please tell what should i do resolve this error.I have
installed DNS and all other
neccassary on the server

Hoping for reply soon

Sanky