Hi, @Rudolf Meier
.rc file is automatically built by Visual Studio. And the .rc2 file is used to store the resources used by multiple different projects.
For your reference: .rc2 file in VS
The RC2 file can be included at the top of the RC file in a project. An RC2 file is useful for including resources used by several different projects. Instead of having to create the same resources several times for different projects, you can put them in an RC2 file and include the RC2 file into the main RC file.
If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.