回复：if it were me or my experiences

About your 3 partitions:

1)Backup OS partition only can be used when OS has problem but still can access the windows, if not ( such as you have no window at all). backup can do nothing. And only can do system recovery. Right?
2)I don’t know why you put all 3 are primary? What is different between you put other two are not primary? In my understand , Primary partition only can put boot OS. But maybe I am wrong.
3)I tried to use easydata recovery but failed , because I should have another computer and put my problemed hard drive as second hard drive then I can do recovery, but I only have a old computer and can’t connect my current hard drive. So I gave up..