Remove grub2 from window partition.

actual command followed by #

1. boot from windows boot media(disk, usb..)

2. select 'repair window'

3. select command line tool

4. # diskpart

5. # list volume

6. # select volume 0(replace 0 with the number  volume of current boot media)

7. # cd ../boot

8. # bootsect /nt60 c: /mbr

9.reboot!