Hi! So my SSD (mid-2012 MBP) crashed a couple days ago. I was running Bootcamp, and it looks like it was the Windows partition that crashed, because I had to connect the drive to a Windows machine to delete and format it. Anyway, i put the drive in an USB enclosure, connected it to my Mac (booted from an external hard drive) and formated the hard drive with MacOS Extended and GUID partition table. I even installed Sierra on it and recovered the latest Time Machine backup i had. Happy days! But wait - when I put the SSD into my Mac (via SATA), it won't show up in Disk Utility. I could boot it via USB, but it wont be recognized via SATA. I tried an old HDD via the SATA cable, and it came up in Disk Utility straight away.. So it looks like the cable is all good! I don't know what to do next..