This has been answered many many times on the forums.
The search function is your friend please try using it, the search on here and goggle to find the answer took me around 30 sec. each.
You don't have the correct .net frame work for the .exe to work , you can either download the 4.0 .net framework and install it or try using the .jar launcher on the same page you download the .exe launcher from and see if that works.
Also Mcafee might block the execution of both the .exe and .jar launchers , if it does either shut off your antivirus or give them expceptions.