I have a dual boot with ubuntu 16.04 and windows 10, ubuntu was installed alongside windows in a same drive. The problem is only 30 gb is allocated for linux and all other for windows. Now i want to add more space for linux system WITHOUT UNINSTALLING UBUNTU Please help
The way to solve this problem really depends on how much you care about your windows partition.
Option 1 - you don't really care about your windows partition:
Shut down your PC with the DVD drive open
Put the Ubuntu live DVD in and boot from the DVD
When your trial Ubuntu boots up start the program called "gparted"
Use gparted to increase your Ubuntu partition. The software is pretty easy to figure out. Right click on the partition of interest and select "resize/move". Make sure you are cognizant of where the partition has data (data is yellow and "assumed" empty is white) and avoid shrinking any partition where there is no white space left!
If at this point your Windows becomes broken, you can always use your Windows install cd/dvd to repair the Windows O/S (on your Windows partition).
NOTE: you may run Gparted from your Ubuntu partition, but then it may give you a hard time because you are trying to do work on a live partition (you have to unmount, the drive you are using, etc...). So you might get away without using a live CD, but why mess around when a live CD is the better way to go? (opinion only)
Option 2 - you really care about your Windows partition:
I don't use Windows 10, but in Windows 7 there is a way to shrink the size of your partition. Right-click "my computer", then select "manage" and from there you go to the "Storage" and open "Disk Management". There you will want to reduce the size of your windows drive. this is important to make sure you create empty HDD space for your Ubuntu to grow onto.
follow the steps outlined in the section above.
NOTE: The Windows work you do may create space on the other side of the hard disk. In that case you will need to use gparted to move the partition, or grow it in the other direction and then shrink it back to the original size.
NOTE: before you do anything back up your data!!! You will grow your Ubuntu partition and that will be easy. If your windows breaks, use the Windows install DVD to fix it - easy. BUT if you overwrite your data that is held by Windows... you will never get it back.
More info can't hurt. Here's another guy with a very similar issue: Give more Hard disk space to Ubuntu