How to: Upgrade Projects to Later .NET Compact Framework Versions
This procedure upgrades the .NET Compact Framework version of an existing project if a later version of the .NET Compact Framework is installed on the development computer.
To upgrade a project to a later version of the .NET Compact Framework
On the Project menu, click Upgrade Project.
If the Upgrade Project command does not appear on the menu, then no later version of the platform is installed on the development computer, and the upgrade process is unavailable for the current project.
Follow the instructions on the prompt that appears.