My application needed a new download Friday 4th, did this 3x and each time 'install or open' took me to File Manager and I couldn't locate the file – rebooting Nokia C7 also did not effect a reinstallation. I deleted the app, then tried again, same story, ended up finding it in a peculiar location (ie not installed files or files to install etc) and when I selected the file (whatsapp_2_6_78.sis) the message was "unable to open, File type not supported" – what is the next step, please?