You are downloading the FB Forever XAP file v22.214.171.124 for Windows Phone. FB Forever is a free Social App: Enjoy the full power of Facebook with Facebook Forever. Full support for photo galleries, news feed, chat, messaging, events and more! Facebook. You can now download the offline XAP package file to install & try it.
Download Locations for FB Forever 126.96.36.199 XAP file
To try to install it manually from an SD card, you should choose one of the server location above to get the offline FB Forever XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.