The installation of the proffieboard might be corrupt. Which instructions did you follow to install the proffieboard board package?
- If you followed the alternative installation method described in arduino-proffieboard/README.md at master · profezzorn/arduino-proffieboard · GitHub, delete the hardware directory where you installed the board package, download the package again from github and try again.
- If you followed the normal installation of the board package (described in https://pod.hubbe.net/proffieboard-setup.html) you can downgrade the package (latest version is 4.6) to something earlier (e.g. 3.6) and see if it works. After that you can try to upgrade to 4.6 again.