Anyone working with web services? I need to know how to impersonate from .NET to a validation file that is an INCLUDE file within a FEX file.

If you are doing authentication within a FEX, you must make the Logon credentials parameters within your FEX. You would then go to the Web Services Description Language (WSDL) creation utility to make that FEX a Web Service function call. The utility will make all parameters within the FEX INPUT parameter to the the new Web Service Function (which is actually your FEX). Go to http://targetmachine/ibi_html/workbnch/webservice.htm to create the WSDL file. Parameters contained within your -INCLUDE fex will also be interrogated.
You can do this from either in a Browser and save the WSDL to disk or through .NET through Add Web Reference. Within your .NET program, Run the WebFocusLogon function to perform WebFOCUS authentication. The result is cookie information contained in the LogOnInfo structure. This would be the first parameter to your newly created Web Service function. The remaining parameters would be the parameters that where originally set up in your FEX.