Restore Dual Boot of Kali and Windows 10

If you are using a UEFI boot system;

You could try installing reefind. It can be installed from windows and will, most likely, find your kali partition.

The installation page recommends www.easyuefi.com/index-us.html.

The original page; http://www.rodsbooks.com/refind/installing.html

If you are using a legacy boot system;

1. Boot the machine using a Live CD.

2. Open a terminal.

3. Find out the name of the inteal disk by using fdisk to look up the device's size. For example:

4. sudo fdisk -l

5. Install GRUB boot loader onto the proper disk (the example below assumes it is /dev/sda):

6. Grub-install --recheck --no-floppy --root-directory=/ /dev/sda

Ref; xeicus on this post

Finding Boot system

Ruing msinfo32 will tell you the boot system somewhere on the first page.