When debugging a program the Peripheral->SystemViewer does not display any peripherals.
Thanks for your answer, I have reinstalled the DFP with packunzip.exe and it works, but this indicates that there is a problem with PackInstaller.exe.
Yes, there was a problem with the PackInstaller (or more precise in SVDConf.exe) in MDK 3.38. You can read the details in the Release Notes:https://developer.arm.com/documentation/107778/5-39/MDK-Version-5-38a
Thanks