ws failing trying to load jdolbhfc.dll

[nathan]

I am just experimenting with Web Service with .NET. I
have created a very simple "Hello World" service to start
playing with it.

When I go to run the service (from the test page on the
method) I get the error:

System.IO.FileNotFoundException: File or assembly name
jdolbhfc.dll, or one of its dependencies, was not found.

The project compiles fine and is as basic as it can get.
Does someone know what causes this?

Thanks,
Nathan