NIs 20.0 incompatible with windows 8.1?

Hi, i recently bought an Asus motherborad and the support CD came with NIS 20.0, i am using Windows 8.1 and when i tried to install NIS it said that it's not compatibel with the OS, i tried running it in comptability mode and with adminitrator rights, but nothing seems to work, is there no way to install it?