Pro Tools users have been experiencing this error message recently on Mac systems. If you recently updated your iPhone to iOS 13, this may be the cause of the error. We have seen a common trend that is affecting multiple plugin manufactures on Pro Tools. This seems specific to macOS Sierra and lower as well.
Please view the following threads:
One user was able to roll back his system using Time Machine to before the problem existed to get up and running.
If you're able to update to High Sierra, this will likely resolve the issue as well.