Even with decades of PC stories about loss, I find that a surprising high percentage of folk don't have backups.
NEVER REPAIR THE ISSUE YOU NOTED UNTIL THE FILES ARE SAFE.
For this one I usually boot up any of the Live OSes I've used over the years.
Read http://tips.oncomputers.info/archives2004/0401/2004-Jan-11.htm and I've been using that for much longer since it's free, works and I don't have to know Linux.
If that doesn't see the files, I pull the HDD out and put it on another PC to run RECUVA.
Now that the files are safe I can try setting it from the command line.
https://www.google.com/search?q=change+active+partition+Windows+command+line&ie=utf-8&oe=utf-8 shows methods I've used over the years.
My daughter did something to my HP ProBook 4430s and instead of doing a system restore, she ended up in the partitions and made the HP partition active. Now, when I turn it on, a command screen pops up and informs me there is no OS installed and to install one. Did she wipe out my primary and recovery partitions or are they still there...hidden or not accessible?

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