I'm installing Kubuntu 26.04 on an existing Windows 11 PC with three drives: the main SSD contains Windows and most applications, a large 11TB hard drive stores my files and Steam library on NTFS, and a mostly empty 222GB SSD is also currently formatted as NTFS. I want to install Kubuntu on that smaller SSD without changing the Windows or data drives. I booted the Kubuntu installer from a USB drive, but when I select the 222GB SSD, the installer only offers manual partitioning. What's the safest way to prepare that drive and create Linux-compatible partitions such as ext4 or Btrfs?
3 Answers
Linux can’t be installed directly onto an NTFS partition. The installer needs space it can format with a Linux filesystem, such as ext4 or Btrfs. You can either remove the existing NTFS partition and let the installer handle the layout, or manually delete it and create the required Linux partitions yourself. Be careful not to select the Windows SSD or the large data drive.
If the SSD contained data you wanted to keep, you’d need to shrink the NTFS filesystem and then shrink its partition to create unallocated space. Do that from the live USB environment rather than from Windows or a running system using the drive, and make sure you have a reliable backup because partition changes can go wrong. Since this SSD is essentially empty, wiping it and using automatic partitioning is simpler.
Since the 222GB SSD is the target and doesn’t contain anything you need, use a live-session partitioning tool such as KDE Partition Manager or GParted. First make absolutely sure you’ve selected the correct drive, then unmount it if necessary and delete its existing NTFS partitions. Create a new partition table and leave the drive unallocated. After that, restart the installer and let it automatically create the Linux partitions. This will erase everything on that SSD, so back up anything important first.
I used KDE Partition Manager and had to unmount the partition before changing it. The installation is running now—thanks for the guidance!