Windows 10 not listed in boot directory on UEFI device after ubuntu installation

[komali2]

Windows 10 is missing from my boot list on my UEFI machine after I installed ubuntu in an empty partition. How can I get it back?


I used a liveUSB of ubuntu to install ubuntu to an empty partition I had created by shrinking the main partition within Windows 10. The machine is a Lenovo y500. Ubuntu boots fine, but Windows is missing from the boot menu, see this image (http://i.imgur.com/R3rd8br.jpg).


I ran update-grub, which yielded the following, rebooted, and found it did not work.



Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.19.0-15-generic
Found initrd image: /boot/initrd.img-3.19.0-15-generic
Found memtest86+ image: /boot/memtest86+.elf
Found memtest86+ image: /boot/memtest86+.bin
Found Windows Recovery Environment (loader) on /dev/sda1
done






Then, I followed the steps on an askubuntu (https://help.ubuntu.com/community/Boot-Repair#A2nd_option_%3a_install_Boot-Repair_in_Ubuntu) link on running a boot repair which yielded this pastebin. (http://paste.ubuntu.com/15010441/)I restarted, and found it did not work.






fdisk -l yielded the following:


Disk /dev/sda: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: dos
Disk identifier: 0xfe621785

Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 206847 204800 100M 7 HPFS/NTFS/exFAT
/dev/sda2 206848 1850200063 1849993216 882.1G 7 HPFS/NTFS/exFAT
/dev/sda3 1952600064 1953521663 921600 450M 27 Hidden NTFS WinRE
/dev/sda4 1850202110 1952600063 102397954 48.8G 5 Extended
/dev/sda5 1850202112 1943949311 93747200 44.7G 83 Linux
/dev/sda6 1943951360 1952600063 8648704 4.1G 82 Linux swap / Solaris

Partition 5 does not start on physical sector boundary.


Partition table entries are not in disk order.

Thank you for taking a look.

[komali2]

Solved, the windows recovery option in the boot menu booted windows without issue.

[oldfred]

Grub has not been updated to search for new version of Windows. The os-prober tries to do a match on versions, and then if not found assumes it is the recovery partition.

Best to never boot into a recovery partition as sometime just booting into it, changes partition table entries, removing Linux entry in table.

One way to fix the descriptions is to move the windows entries to 40_custom and edit at will.
http://askubuntu.com/questions/659528/grub-menu-with-windows-10-and-ubuntu-14-04/659910#659910

Copy the entries from this:
sudo cp -a /boot/grub/grub.cfg /boot/grub/grub.cfg.backup
gedit /boot/grub/grub.cfg
Copy them to and edit to have only entries you want:
gksudo gedit /etc/grub.d/40_custom
sudo nano /etc/grub.d/40_custom
Then do:
sudo update-grub

gksudo gedit /etc/default/grub
#Add this line:
GRUB_DISABLE_OS_PROBER=true
sudo update-grub