John I bet they didn't build the .net dll with cominterop options but you can always try to do the following
open command prompt
type in the command c:\windows\Microsoft.NET\Framework\v2.0.50727\regasm.exe /codebase "c:\program files\....path and filename.dll"

assuming regasm run without any prb
in VFP go to the Intellisense manager Types Tab and press the type libraries button, look for the class you just register.
Now you can use it in VFP

If this doesn't work cause the .net Assemblie doesn't support cominterop, what you will need to do is create a .net wrapper that will use that assembly and compile it for com interop.

>I am trying to access a .NET DLL from VFP 9 and need some help.
>
>We have a management system entirely written in VFP 9. We are looking at interfacing with a payroll program. The company that developed the program provides a .net dll that allows third party software to fully access the program. This makes it very attractive to us as it allows us to send and retrieve data without the user having to do the normal import/export on both ends.
>
>The help file states: The (SDK) consists of a .NET class library that provides access to the data.
>
>The SDK comes with a sample Visual Basic project. I downloaded VB Express and was able to compile and run the sample program. From VB Express I can open the DLL and see the methods, properties, etc.
>
>Having spent some time the past two days researching this I can now say with confidence I really have no idea as to what to do to get VFP 9 to interface with this blasted DLL. It appears that I need to create a COM program on the VB side but I am lost at this point.
>
>Where do I go? If this is not an easy task I would even pay someone with the knowledge and tools. (Warning: The budget is tight right now.)