The only version of Intel(R) Rapid Storage Technology that was posted on downloadcenter for third party motherboards and Original Equipment Manufacturer computers was version 12.5.
Still, your problem seems to be more related to a corrupted driver installation, which could happen with any version release.
You may try using the version provided by your system manufacturer and install it on top, or try using a registry cleaning tool and remove any entries related to that driver. otherwise an operating system repair/re-install would be required
Thank you for the answer Diego !
Actually Intel had released the 12.6 version and removed it afterward. So now the 12.6 release is available on a few drivers websites, it is why I downloaded it.
But I found where the issue came from ! There is a compatibility problem between the Intel Rapid Technology and the Intel Device Software driver (Xeon). I can't install both of them so I chose to install the intel Rapid only.
This way it is working nicely...