Usually laptops have soft keys , try removing the keyboard clean it reinstall it and try (dust and ants can cuse it).....if not work take it to service centre it needs repairing
this problem came to me too
i just removed the idm and installed youtubedownloader hd
see sometimes this idm can meke problem you can always reinstall idm but if that didnt work try insatlling youtubedownloader hd
and download the video
may be you should go to control panel and search for internet connections and click it and it will have something saying network....
click it and select the support tab and click repair
that did the trick to mine