Computer specs:

Hp elitebook 8740 w i7 q740 1.73ghz 6MB cash 2.93 Max ghz 8 gigs Ram 500 gig hard drive Nvidia Quadro 5000 m 2 gigs gddr5 - windows 10 64bit

Problem:

I'm downloading Dradtsight 64 bit and having trouble with installation. When I click on Dradtsight.exe it starts installing and then error message "installer package can not be opened". Any help would be much appreciated. Thanks