We try, I say to my wife "we aim to please, but sometimes we miss the target"
G'day Chris, you lucky dog, you got me again.
Basically, you are right. It's a safety feature of GParted, one of my all-time fave tools.
Partitions are mounted in order for Linux to use them, and they could be:
- The partition your OS is on, aka / or root
- The partition, in a UEFI-based PC, is the EFI System Partition (ESP)
- Your system has a command in place somewhere, that mounts (removable or not) drives automatically
- Other (means I cannot think of anything)
If you are looking to work on your root partition, your system is running on it, and so you cannot unmount it, therefore GParted functions such as resize, remove, label, name &c will not work.
3 ways of getting around this - order is arbitrary -
- Have another Linux as well, on your PC, you can use the GParted of one to manipulate partitions on the other and vice-versa (which is what I typically do)
- Have a GParted Live USB stick or DVD
- Have your original install USB stick, or indeed just about any Linux Distro's install stick that can accommodate GParted (usually already on there, outside of the installer itself), on hand.
On 1. - You might have Windows x (7, 8 or 10), Linux Mint, and Ubuntu (or try Manjaro for a change of scenery)
On 2. - GParted Live will fit in a space of less than 500MB (I have it on my first ever USB stick, 512MB and just update it periodically), and so it will also fit on a blank CD if you have one kicking around.
On 3. - Boot up your Live USB installer stick, and
don't start the installer. If you are going to be doing a few operations, you might want to disable in Settings the screensavers and power savers so the screen is on all the time. In the start menu, start to type in
gparted
and you'll find it.
GParted Live is here
https://gparted.org/livecd.php
Ask any questions.
Also see my vid here
https://www.linux.org/threads/gparted-partitioning-for-linux-read-this-if-you-need-help.22028/
Any questions, ask here or there, and tell us what you want to do.
Cheers
Chris