How does a ClickOnce application know where to check for an upgrade?

I have a ClickOnce application that is set to "Online Only". In other words, the .appref-ms file does not come down to the client (this file carries point-of-origin information).

However, the ClickOnce application uses the 开发者_StackOverflow中文版System.Deployment.Application.ApplicationDeployment class to check to see where there is an update available.

How does the application know where to check for an update, if the .appref-ms file does not come down to the client?

Check registry: HCU > Software > Microsoft > Windows > Uninstall > #yourappid# > UrlUpdateInfo

cdf-ms files and executable manifests are going to a client anyway. When ClickOnce launches, the manifests are telling it where it can get updates from.

They are in C:\Users\USER_NAME\AppData\Local\Apps for Windows 7 and C:\Documents and Settings\USER_NAME\Local Settings\Apps\2.0 for earlier versions.