Make Win8 partition bootable again

This is the situation. I have a HDD and a SSD in my laptop. Both have Windows 8 installed. A few days ago I tried to boot the HDD one and I got the windows screen saying there was some kind of problem and it was trying to fix it. It wouldn't pass the 45%, no matter how many times I tried. So I think, I'll boot the SSD and fix the problem from Windows. I opened the disk administrator and selected the windows partition in the HDD (there are other partition, recovery, drivers and stuff like that), I scanned it and it found some problems and fixed them. I thought that was it. But no. I shutdown, and try to boot from the HDD. I don't get the CHKDSK screen. It just jumps to the SSD and boots.

And now I can't access from the SSD Windows to the HDD (I could before). I tried to fix it with a Win8 installation usb and following the guides I found in the internet and I can't get to fix it. I get messages saying that no windows installations are found. I get error 0xc0000225 if I remove the SSD. I'm sure I'm missing something, some step or something like that. So here I am asking for help.