Go to the Packard Bell support web site here:
http://support.packardbell.com/uk/
http://support.packardbell.com/uk/item/index.php?m=step3&i=platform_sjv50_pu2w
http://support.packardbell.com/uk/item/index.php?pn=LX.BEU02.001&g=2000
Download the Easynote Touchpad driver and the Easynote Launch Manager.
I'm guess that the Easynote Launch Manager is the software that controls the hotkeys, so try that and hopefully reinstalling it will resolve the issue.