It can be very handy to install Psion application .SIS files directly on the palmtop. If your Series 5 doesn't have 'Add/Remove' as an option already in its Control panel, then transferring this file, INSTEXE.EXE file to your Psion (e.g. on CF card or via My Psion) and then tapping on it in System will install the plug-in and then delete the .EXE automatically.