This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types like documents, projects etc. This type of file is no longer actively used and is most likely obsolete.
This ppf file type entry was marked as obsolete and no longer supported file format. The ppf file extension was used by older program Micrografx Picture Publisher. There are 8 other file types using the PPF file extension! Graphics file type.
