Microsoft Anniversary puts the screws to the partition table

I recieved a question when someone asked about why a person had two MBRs. I guessed it was related to the new kernel structure in Windows 10 aanniversary edition. Here is my answer: Hello, I have four theories about what could be temperamental.

The first two have to do with applying Windows update 1607 also known as the Anniversary update:

Theory 1:

Have you tried to restore using an older media? If so the computer might have thought that the updated boot record could be from Linux and written a new MBR. source: http://www.easeus.com/partition-manager-software/windows-10-1607-update-stuck.html

It might be looking at the C partition which might have been accidentally set to active. According to the article here: https://www.partitionwizard.com/partitionmagic/accidentally-marked-drive-c-active.html

Theory 2:
The second question I have for you is Do you have Linux distribution on this disk or have you ever used this disk for any Linux distro?

Explanation: In the Windows 10 anniversary edition Microsoft reworked their kernel to make it more like Linux. The update has thrown many people off guard who have have used other operating systems along side the Windows system. This has been particularly troublesome for those who use LVM (which stands for Logical Volume Management. It is a system of managing logical volumes, or filesystems, that is much more advanced and flexible than the traditional method of partitioning a disk into one or more segments and formatting that partition with a filesystem).

Theory 3:
Question: Have you ever had success with Windows 10 and the current combination of motherboard and other hardware you are using?

If not: Check your hard drive in Disk Management , is windows installed to a GPT or MBR disk. Mine is MBR. You can't install Win 10 on UEFI firmware with secured boot enabled and CSM disabled if the disk is MBR. The disk has to be GPT. Is it possible for you to tell us a little about who made your computer (for example Dell, HP so we can help look at the motherboard manual)

Source: https://www.cnet.com/forums/discussions/no-csmsecure-bootuefi-options-in-bios-cant-install-win10/

Theory 4:
Have you ever used or attempted to use bitlocker on this computer.