>It's just a guess, but it might have been related to pathing.
>When I run it manually it uses the pathing established with my log in.
>To get the app to run as a service, I had to change all the network drive letters in the app.config to their natural equivalents.
>The app might still have been looking for the report viewer on a network path.
>Including the report viewer in the app avoided that issue, if it was one.

That would certainly be something to check.

I try to universalize all that at the application setting level. Thus, if it work on one specific interface, it should work on another.

I use UNC approach everywhere. It turned out to be a good approach so far.

One other thing to consider is to always have a universal startup path that your application can rely on. Thus, from a global setting the application reads at startup, you can access the related directories from the same root path, no matter from which interface the application got started.