You are downloading the Letters generator AppX file v220.127.116.11 for Windows Phone. Letters generator is a free and useful Entertainment app: How about sending that message or that wink with a different and personalized letter.Now it is possible. With several ... You can now download the offline AppX file to install & try it.
Download Locations for Letters generator 18.104.22.168 AppX file
Note: To install it manually from an SD card, you should choose one of the server location above to get the offline Letters generator AppX file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.