I am currently dual booted with Windows 10 and Ubuntu 16.04 LTS, I had provided ubuntu with a petty 70 gbs and alloted the remaining storage of my 500 gb(i.e around 420 gbs in three partitions) HDD to windows 10, but recently I have been using ubuntu alot, now I think 70 gb is quite small for the usage I have.
So I want to reinstall ubuntu by taking 1 partitions from windows and merging it existing ubuntu partition and then reinstalling. In that way I won't be losing my windows data.
Is there anything I need to take care of before proceeding to this, as I recall I might encounter a problem which will disable my access to windows into boot/grub menu or vice versa.
How do I avoid such instances?