[SOLVED] System won't boot from new drive

[That Potato]

So I got a new drive for my brother to migrate his OS over to. I wanted to keep some files, so I loaded up the new drive with a usb stick to get a clean install of windows on it. I then booted the system from the new drive, and transferred all the files that I wanted to keep from the old drive onto it.

Now this is where I get stupid so please forgive me.
I wanted to still keep the Steam games on the old drive, because I didn't have enough room on the other one. So I changed ownership on the windows files and deleted everything from the drive except for the steam games. I was still running into problems with the system crashing and not booting from the correct drive so I then installed some software to delete the system partition and recovery partitions to see if that's what was causing the problems.

After I deleted the partitions from the old drive the system will no longer boot and I'm all out of ideas.

There is a fresh install of windows on the new drive (except for a few save files and pictures from the old one that I still want to keep), but it just won't boot from it and I don't know why.

The new drive is a 500GB SSD and the old one is a 1TB HDD

 

[That Potato]

I have fixed the issue.

I took an old drive that had windows installed on it and booted it from there. I then transferred the files that I wanted to keep onto there from the new drive.
After that I booted from a USB and formatted the new drive and freshly installed windows on it again with no other drives attached (I think that having the old drive with windows installed on it was the problem last time).

Anyway, I transferred the files onto the new drive, and rehooked up the the drive with the steam games on it and everything seems to be working fine now.