I have a customer who I wrote a piece of software for. The software is a windows app, but downloads information needed to run via a webservice I host on my webserver.

Everything works great, except sometimes they go to install the software on one of their customers PCs, and the software can't hit the web because of a firewall.

I know most half decent firewall programs will generally prompt the user for access to the web when the program tries, but apparently they have run into some situations where they can't find what software is blocking the app (and these guys are NOT computer guys. I am sure if I was there I could find the offending firewall app, and allow the access, but these installs are done all over the country, and it was only my job to write the app for them)

So anyway, I am wondering if there is anything I can do to try to avoid this scenario.

Is there anyway to probe what apps are blocking connections? or anything you guys can suggest to make this a little more user friendly?