If I deploy a new version of my application, will the user lose all the settings saved by the previous version?

It is easy to upgrade settings from a previous version of the application to the latest. Simply call ApplicationSettingsBase.Upgrade() and it will retrieve settings from the previous version that match the current version of the class and store them out in the current version's user.config file. You also have the option of overriding this behavior either in your settings class or in your provider implementation.

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