When I used the "Download Your Information" feature of Facebook, it produced two zip files. Both files have a messages folder and a large file named facebook_1479114225.zip.enc. There are no instructions as to how to join these two zip files. I cannot just extract the contents of both files into the same directory as the second extraction would overwrite the first large .enc file.
Only one of the files contains an index.html file and I am able to access that page to read contents going back several years, but I have no idea how to merge these two files.