I installed Ubuntu on my spare HDD and everything was going fine until the setup installed GRUB. I have 3 HDDs in RAID0 and a spare HDD where I chose for Ubuntu. The error said that GRUB cannot be installed on drive named "sda", therefore I picked "sdd" from the list, which was the HDD with Ubuntu on it. As I went through the list of drives, I noticed a few volumes with "mapper" in their name, which I assumes is the RAID0. Afterwards, even though it was installed on a separate drive, I had to use the /fixmbr windows recovery to be able to boot into windows.
My question is, why did it still affect windows if it was installed on a separate drive? When it was trying to install on "sda", does that mean it might have corrupted my windows partition and data?