You are downloading the WinSoft Search AppX file v22.214.171.124 for Windows Phone. WinSoft Search is a free and useful Productivity app: Search the Web more easily using WinSoft ... You can now download the offline AppX file to install & try it.
Download Locations for WinSoft Search 126.96.36.199 AppX file
Important Notice: Now Due To Unspecified Limitations, You Can Not Use The Offline AppX 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 WinSoft Search AppX file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.