With all the Windows fixes it probably is the Windows bug (Windows may call it a feature?) that re-writes the partition table but conveniently forgets to include Linux partitions.
If not then we need a new Summary report from Boot-Repair.

Windows 7 to Windows 10 MBR partition missing
http://ubuntuforums.org/showthread.php?t=2288988 &
http://ubuntuforums.org/showthread.php?t=2290190
http://ubuntuforums.org/showthread.php?t=2292545
Use parted rescue to restore missing partition details in post #22
http://ubuntuforums.org/showthread.php?t=1775331
https://www.gnu.org/software/parted/...ed.html#rescue
http://gparted.sourceforge.net/faq.php/#faq-22
Parted rescue seems easier than testdisk
https://askubuntu.com/questions/6654...untu-partition