Editing Lenovo ThinkPad P1 (section)

==== Shrinking it from within Windows (RECOMMENDED) ====
'''WARNING: IF YOU HAVE BITLOCKER ON A DRIVE, YOU MUST HAVE YOUR WINDOWS BITLOCKER RECOVERY KEY IF YOU WANT TO SHRINK THAT WINDOWS PARTITION ON THAT DRIVE. OTHERWISE, FIND A DIFFERENT HARD DRIVE OR YOUR DATA WILL BE LOST. YOU HAVE BEEN WARNED!'''

Now shrink your drive within Windows by pressing <code>Windows+R</code>, typing <code>diskmgmt.msc</code> and pressing ENTER, then finding the NTFS partition you want to shrink (it's usually a big 250GB chunk you see on the screen) and right click > Shrink and shrink the partition by ~30GB or so for installing Ubuntu. (Don't create another partition on top of the "Free Space" that's now there. Just leave it be.)

If diskmgmt.msc complains with an error saying "the partition cannot be shrunk" or similar, you will need to follow the steps in [[Shrinking Windows partitions for installing Linux#Defragmenting the partition]].