Same problem for me after I'd paid my 1 day subscriptioin fee for Sport. I deinstalled all Nowtv apps & links , restarted windows, started Microsoft Edge. Used 'wathc.nowtv.com/sports. Logged in. Checked my money was still there OK. Went to 'Help'. Downloaded app from here. Clicked downloaded exe to 'run'. Completed installation. Went to screen I got just after 'Help'. Clicked 'Ive alreadyinstalled this' , then clicked on my selected cricket game & it worked ok. I'm running Windows 10 version 1803.