Does anyone know what can cause NTLM authentication issues when there are multiple authentication attempts to Client Access Servers attached to a hardware load balancer or multiple load balancers? This is mostly happening when an Outlook Client is trying to connect via Outlook Anywhere (RPC over HTTP), on re-authentication attempts, the user keeps getting prompted to enter in their Active Directory credentials. This only happens when the load balancer(s) is attached to the CAS server(s) and are in an array. When the load balancer(s) are not in the picture, NTLM authentication works fine. Any help would be appreciated. Thanks.