We have an industrial system, which can be interfaced using some C++ DLLs given to us. I wrote a .NET wrapper to control the industrial system, then bundled this .NET wrapper into an ASP .NET web application so we can control the system over the web.
Everything works fine when I run/debug in Visual Studio using the ASP .NET Development Server. When I deploy to the local ISS server I'm getting an error from the C++ DLLs that (I'm told) means that there's a communications fault.
Because the IIS app and the Dev Server are on the same machine, and one works and the other doesn't, I'm convinced that this is a permissions/security error. I've spent days fiddling with Application Pool identities, ASP .NET impersonation, filesystem permissions etc. to no avail. (I'm also a bit of an IIS-noob, which doesn't help.)
So, here's the punch-line:
Could somebody please explain how (if it's possible) to set up an IIS ASP .NET application so that it's running with full (balls-out, guns-blazing) access to the local machine? I want to ensure that IIS is not holding the application back by anything.