In addition, within the Pinnacle folder you will also find a Scratch folder that holds data for all the version of the program
The folder of interest within the Scratch folder is AppData>Local>Pinnacle>Studio>Scratch>NGThumbnails. If your library has red thumbnails even though the assets are OK (often caused by importing video before the codec for that format has been activated), then deleting this folder will cause the thumbnails to be re-generated.
Rebuilding the effects database
Returning to the 16.0 and 17.0 folders, AppData>Local>Pinnacle>Studio>16.0/170.0>EffectsDB contains a file called EffectRepository.xmp. Deleting this will force a rebuild of the effect, titles, menus and other “fixed” assets of the version of the program you selected the folder for. If you think you are missing some effects, this is the file to delete.
AppData>Local>Pinnacle>Studio>16.0/17.0>NGDatabase holds all the Library data. A corrupt library can cause Studio to crash or even refuse to run, but if you delete the folder you will lose all your metadata. If you want to back up your library, this is the folder to copy. Save it somewhere safe, and replace the current version with the saved one to restore you library.
Reverting Studio to the default settings
AppData>Local>Pinnacle>Studio>16.0/17.0>Settings holds Settings.XML, and this includes the setting that causes Studio to try to load the last project. If that project is corrupt, then it can be causing Studio to crash. There may be other things that deleting the settings file will fix. It will reset the watchfolders and give you a chance to change the settings when you next restart Studio, so if a corrupt or non-compatible file is causing problems this will allow you to eliminate it being automatically included.
You will have noticed there are some folders I haven’t mention because I only suspect, rather than can prove, what they do. However, if you want to do a complete reset which will affect things such as Audio waveforms, Stabilisation data and so on of both versions of the program, delete the whole of the AppData>Local>Pinnacle>Studio folder.
AppData>Local>Avid>Studio>Scratch>Render will contain the Preview Optimisation files (assuming you haven’t altered the default program settings). These files are sometimes called render or auxiliary files. There may be other files here as well, built up during disc export and other processes, so if you want to be sure that you have deleted all the render files, delete the entire folder structure.