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HOWTO: Authenticate Active Directory account over VPN from C# client?

Posted By:      Posted Date: September 20, 2010    Points: 0   Category :Windows Application


I have some code that authenticates a user in Active Directory from a C# client but it does not work through a VPN connection, though it works just fine when I'm connected to the network.  How can I get this to work over a VPN?

These are the three functions I've used that ALL work, just not when I'm connected through a VPN.


        public static bool ValidateUser1(string strDomain, string strUsername, string strPassword)
                DirectoryEntry entry = new DirectoryEntry("LDAP://" + strDomain, strUsername, strPassword);
                object nativeObject = entry.NativeObject;
                return true;
            catch (DirectoryServicesCOMException) { }

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