[RESOLVED] Installation Failed

[Snowhog]

I created a virtual machine (Oracle VM VirtualBox Manager). I accepted the Unattended option. During installation, I opted (as I always do) to manually setup the partitioning. I specified gpt and created a 512 MiB FAT32 partition with the Boot flag set, specified /boot as the mount point, as there wasn't a /boot/efi in the list. I added /efi to the selection so it read /boot/efi.

I used the remainder of the drive space for / as btrfs.

At the end of the installation an Error window popped up:

Installation Failed

Bootloader installation error

Details:
The bootloader could not be installed. The installation command <pre>grub-install --target=i386-pc --recheck --force /dev/sda</pre> returned error code 1.

Why? Should I have left /boot as /boot and not modified it to /boot/efi?

[Snowhog]

While waiting for an answer, I'm redoing the VM. Still gpt. Still manual partitioning. But this time creating an unformatted 8 MiB bios-grub flagged partition, and the rest on / for btrfs. Installing now. Just finished installing (All done. screen). No pop-up error. Restarting it now. Booted into 24.10 without incident.

So why the difference in partitioning requirements for Kubuntu vs KDE neon?

[Qqmike]

Have never used either a VM or btrfs. But I'm noticing something that may be OK, IDK.
You are mentioning two things that caught me eye: i386-pc and bios-grub.
That's for Legacy GRUB, right? It's not for EFI (GRUB2-EFI).
However, you also mentioned trying to send boot files to an EFI folder (boot/efi).
Could this be a clue to the issue?