I'm trying to shrink the main drive's partitions to set up a dual-boot with Linux, but I can't get the partition to reduce beyond 138GB. I've followed instructions from an archived post but have had no luck. I also tried using Paragon Partition Manager, but it keeps telling me to reboot, and nothing changes after that. It's really frustrating since this seems like such a basic task. All my PC info is in French, and I've linked a screenshot for reference.
2 Answers
When trying to resize a partition that your system is actively using, keep in mind that you can't go beyond the last file on that drive. The best way to tackle this is by booting from a Linux installation disk (like a live USB) or another Windows installation media. That way, you can manipulate the partitions without any restrictions.
Exactly, you can’t alter the partition that’s in use. I recommend giving GParted a shot; it’s a great tool for resizing partitions from a live environment.

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