SOLVED Dual boot destroyed

[nvsoar]

For info - Please be advised that the 12Jan2016 Windows 10 Home update destroyed my Ubuntu dual boot by labeling the Ubuntu partition as 'unallocated'.

 

[Saltgrass]

How were you booting the system, Windows or Grub?

Could we get a picture of your Disk Management window to see its configuration?

 

[nvsoar]

System used Grub2 boot with Ubuntu installed in an extended partition. After the Win10 update the boot choice was Win10 only. That wasn't much of a surprise. However, Gparted showed the Ubuntu partition as unallocated and the swap partition intact. Was able to recover the Home file with Test Disk. Have reinstalled Ubuntu; system operates normally.
Surmise that Win10 takes it upon itself to 'clean up' the boot. What surprised me was that the Ubuntu partition was removed, which I interpreted as malevolent behavior and worth advising the Win10 community of my experience with the 12Jan2016 updates.
Was not aware that the Windows boot process could recognize the existence of a Linux system.