The sofwtar will never erase these files, so if they were eraser then something else must have done this.some other things happend in the system folder,; the extensions was erased, I can see other folders being emptied to... cliparts, iconlibrarys, the settings for the ftp in the publish tool are also gone?
Note however that the lightboxes should not be in the system folder. They should be in the application folder.
This folder contains user files, like documents, templates, extensions and publish settings. Normally, this folder should not be deleted because then you will loose all your work and configuration.If I erase the "Wysiwyg Web Builder" folder from the Documents folder before installing the latest update 17.1.1, do I get a clean installation then?