You should be installing 10. You can do that with your 7 key.
Regardless, get the latest drivers from here: https://downloadcenter.intel.com/download/25165/Intel-Rapid-Storage-Technology-Intel-RST-RAID-Driver?product=55005
File: f6flpy-x64.zip. Unzip it to a folder on a USB drive and hit "have disk" when that error appears and point it to where you have those files. After it does it's thing hit refresh.
This is assuming you are using a disk. If you are installing from USB there may be another cause.