Please restore the app to factory defaults. Here is how:
1. Quit Protect Files if it is running.
2. Hold the Option key and use the “Go” menu in the Finder to Show Library
3. Delete these files and folders if they are present:
To reset all the app settings:
~/Library/Preferences/com.apimac.ProtectFiles.plist
~/Library/Preferences/com.apimac.ProtectFilesHelper.plist
To reset all the app data:
~/Library/Application support/Apimac/Protect Files/
4. Launch the app in order to recreate from scratch the resources it needs.
See also:
How to access your data without launching an encrypted space