You are downloading the Sighty XAP file v188.8.131.52 for Windows Phone. Sighty is a free and useful Social app: Sighty provides second life users an easier, faster as well as a more mobile way to check their friends' status and groups' profiles.Notifies ... You can now download the offline XAP file to install & try it.
Download Locations for Sighty 184.108.40.206 XAP file
Important Notice: Now Due To Unspecified Limitations, You Can Not Use The Offline XAP File To Install It Any More.
To try to install it manually from an SD card, you should choose one of the server location above to get the offline Sighty XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.