Your drive may be fine. I ran into the same thing with my laptop. I'm still learning about this stuff, but apparently the migration software won't support usb-to-sata -- it won't recognize the drive. So you'll need to use a different cloning software -- there's more than one free app, I used Macrium Reflect Disk, which worked fine with a little tweaking. I had to clone one partition at a time because I was going from a larger to a smaller disk, but once I figure that part out, it was OK.
Now, of course Win 7 needs to see your drive. In my case, Win 7 didn't seem to see it since it didn't show up in Windows Explorer. But, when I went to Control Panel/System and Security/Create and format hard disk partitions (under Administrative Tools), the drive was there as a blank volume. I did a quick format and the disk came alive as the D drive. Intel migration still didn't see it, but Windows did, and from there I was able to clone.
Thank you so much for answering my question. You were right in that I needed to go into the format disk partitions and do a format for it to show up, as well as needing different migration software.
I really appreciate you saving me the headache of saving a perfectly fine drive back!
I'm glad it worked.
I've now installed a couple of these as boot drives (on my desktop and laptop), and each time the process of getting them up had a few more bumps than I hoped for -- Intel's instructions and software could be better. (I'm 0 for 2 with Intel's migration app.) But persistence paid off, and the drives themselves are great -- I'm getting the speed I was hoping for.