Did you previously move the application using the homebrew program mvapp? If so, you need to unlink the app and restore the app to the default location:
Open Terminal (found in Preware) and type "mvapp s shop" to find the application.
Then do an unlink and run Preware's Emergency Migration Helper.
If you ran 'cleanup' and have a 'backup', you can run 'mvapp
restorebk',
which puts apps back in /media/internal/.apps. Then repeat search
command above.