Today, I had create a deployment procedure for a VSTO 2007 Excel Add-in. Since I'm not an expert in Office-related development, I started doing some research on the topic. Here's what I found out to be the best way to do such a deployment. (Note, again, I'm a rookie at Office development, so there might be better ways...)
Initially, I found the most easy way to deploy an add-in is using the Publish function in Visual Studio 2008. This way, a ClickOnce is created.
Now, the add-in connects to a lot of WCF services. The addresses of the endpoints of these services, among other configuration information, is stored in the app.config from the add-in. This information needs to be editable, since the server address might change over time.
When using the ClickOnce setup, the deployed application worked fine. The application was able to read out the settings of the app.config file. However, it is not stored in a specific location, since it is in the cache of ClickOnce. So, I had to find another solution, so that the config file can be located and edited.
So, after doing some more research on the subject, I found the correct way to deploy an add-in is a simple setup project created from Visual Studio. However, you need to add some registry settings as well as some other configuration.
The complete procedure is explained here and here.