“ClickOnce” deployments reside on either web or file servers. The standard methods & techniques used to scale those types of servers can be used for “ClickOnce” applications. For example, large web application will often be hosted on some type of server farm. “ClickOnce” applications can also be hosted in such an environment.

The main thing to keep in mind is that “ClickOnce” apps will have slightly different needs. Compared to a web applications, most “ClickOnce” applications will need fewer server CPU resources ( the server is just serving up static files). In addition, normal activation of a “ClickOnce” application is very inexpensive for the server & network. The biggest scalability consideration with “ClickOnce” is the network bandwidth needed for initial application deployment & application updates.