Yesterday I had to try installation of new Ubuntu 15.10 more than 5 times.
I have noticed methods that give me unbootable system on reboot after installation. It says it cannot detect UEFI partition even if it exist and is made during same installation time.
- If I upgrade from 15.04 to 15.10 using Bootable CD, if ways half way saying it cannot detect UEFI partition
- If I install using
Something Elseoption during installation, it fails on reboot.
The only way for me to get bootable system was to erase whole hard drive and let it make all partition by itself (lost most of my data :'( forgot to backup in frustration)
I am very much confirmed of what I experienced yesterday (whole day) and I am pretty much sure that there is a bug in installer, so how do I report a convincing bug-report to Canonical?
https://bugs.launchpad.net/dell-sputnik/+bug/1499323 It is most likely related to this bug, it is actually a bug in some uefi firmware that they specifically look for the windows only uefi entry point. Follow the steps in the bug work around and see if that fixes it for you
First to answer your question - file a detailed bug report on launchpad containing the steps you attempted and an explanation of all problems you experienced during the installation process !
You have to know that Canonical tries to build the installer making it as convenient as possible for all users with different levels of knowledge concerning partitioning and boot procedures.
In most of the cases the issues are generated by the users themselves doing something wrong.
So before providing your bug report on launchpad please try the following installation method.
Step 1 : Backup the data you want to keep to an external disk or a separate partition.
Step 2 : Create a proper installation media using Brasero for DVD or Disks for USB.
Step 3 : Prepare the partitions using GParted by formatting the system partition.
Step 4 : Start the Ubuntu installer and choose Something else from the menu.
Step 5 : Select the the (clean) system partition for root you formatted before.
Step 6 : Select the correct disk for the GRUB boot loader to install it to.
What reads as "I already know this" instructions ... if you carefully prepare all things before starting to install a new Ubuntu edition, only in very rarely something will not run smoothly.