TABLE 4   ITEMS TO VERIFY FOR INTERNAL CLIENT ACCESS
Item	Description	Client Type Affected
Network connection	Ensure that the physical and logical connectivity between the client and server is working properly.	Both
LAT	Ensure that the internal client’s IP address is in the LAT.	Internal
Protocol	Ensure that the requested protocol exists. This applies to the WinSock Proxy and Socks Proxy services.	Both
Permissions	Ensure that the user has the ability to access the requested protocol. This applies to the Web Proxy and WinSocks Proxy services.	Internal
Packet filtering	Ensure that packet filtering isn’t restricting access.	Both
Domain filtering	Ensure that domain filtering isn’t restricting access.	Internal
Service provider restrictions	The requested resource provider may be restricting access in some way. For example, if the client is trying to contact an IIS computer, the server itself may be denying access. Clients can be denied access based on domain and IP address restrictions, NTFS restrictions, Web site restrictions, and/or virtual directory restrictions.	Both
Reverse hosting or Reverse	The requested URL must be supported by one of the internal servers and the Proxy Server must be proxying correctly configured to pass the request.	External
Wspcfg.ini for internal servers	If the service provided is not an HTTP service, then server proxying must be used. This involves the use of a wspcfg.ini file in the directory of the service executable file.	External