Short version
I reinstalled Ubuntu 15.10 on my Dell XPS 13 (Option: Erase disk and install Ubuntu) but on boot, I have a message that no bootable system has been found. When I display the boot options and select the SSD ('Legacy'), UEFI says it's not bootable (Ubuntu installed in UEFI mode).
How can I fix this? (Reinstallation is an option)
Context
Upgrading 14.04 to 15.10
I had some minor quirks with the installed 14.04 and wished to upgrade. I just used the settings so that Ubuntu would upgrade to the latest version, which worked. But I did not have any network available.
15.10 Fresh install, legacy mode
I went for the clean install (USB stick, Unetbootin) and that's when I think I made my real mistake: selecting the Erase disk and install Ubuntu option.
Since then, it does not boot. I was able to boot it manually from boot menu, but saw that the UEFI section under which Ubuntu was previously visible has now disappeared.
15.10 Fresh install, UEFI mode
I tried reinstalling it in UEFI mode, but no luck. I was afraid the system scraped a partition used for boot, but no, an efi partition is present (Ubuntu actually mentioned he would write an ESP partition before doing the partition changes).
Booting in Legacy mode is no longer an option (obviously...).
The BIOS (updated to the latest version Dell supplies, from November 2015) does not seem to see the UEFI partition. When going through the settings and trying to add a BOOT option, though, I can see the Ubuntu part, but it fails to be added.
And now?
Is there any right way to fix it?
RESULTS.txt
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