Which files to use for update

Hi people,
Have a small application (forms) that I want the clients to be able to update.

I am using one location on the server to store updates, and one for the original installer zip. Could this be a problem, in that both need to be in the same place?

The app is in its infant stage at the moment, but I'd like to get it to update from day one.

Which files do I need to put on the server in order for the app to update. At the moment I've tried the '*.application' file, and the 'Application folder' & its contents.

Any guidance would be appreciated.
Regards
Les

need more info please

I have set the publish folder to a local drive on my PC, and have set the update folder to be on the network (server).
The publish procedure works fime and places the setup files on my PC, and installs fine. I've also got a colleague to check that it installs from his machine, which was also ok.

Upon running the published app it as expected checks for an update, and I assume because there is nothing in the server location folder, then it just loads.

When I now make changes to the original app files and republish, which files should I put on the server?

I have made the tests as mentioned in my first post, which doesn't work, but have I even got the concept right?

regards
Les

BTW: I'm using 2010 Express, but should the need arise, or becomes a pain, I do have the full version of VS2008. So before I get too far down the road, It won't be too much of a problem to revert abeit by hand.

Polite bump... :) (just in case its been missed of course.... you understand)

I'm not nagging anyone, but this problem hasn't gone away. As this is my favourite site I'm reluctant to start trawling other sites. If I don't comment it will get lost in all the other pages. So I'm just posting to let you know I'm still interested in an answer, should anyone know & find time to reply.
Thanks again peeps. :)