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flintdk
February 20th, 2013, 01:58 PM
Hi folks,

I'm trying to install Ubuntu 12.10 64-Bit on a Windows 7 laptop:
-> The laptop is a Lenovo Z580, it has a UEFI BIOS and is set to boot in UEFI only mode (legacy support is not enabled)
-> Secure Boot is not enabled (it's currently running Windows 7).
-> There's a good chunk of free, unpartioned space on the disk ready and waiting for Ubuntu.

Ideally - I'd like to dual boot Ubuntu and Windows 7. But when I install Ubuntu it doesn't detect Windows 7 (I get a message "no operating systems detected")) and the only options available to me are to erase the entire disk or "something else" (i.e. a manual install).

I had a look here before I registered and saw a couple of posts similar to this - but the fixes suggested don't seem to apply to my situation (e.g. tinkering with "dmraid" - I don't have a raid controller).

I appreciate there's probably not enough information above to help diagnose the problem but if someone suggests some extra information I could post... then I'll post it. I'll admit - I'm new to Ubuntu (as in totally, utterly new). But have been using different OS's for years, some linux based, so happy to dig around for answers.

flintdk
February 20th, 2013, 02:02 PM
Nuts - just spotted another message about a utility "fixparts" - hadn't seen that one before. I'll download it, try it from the live CD, and post the results.

offgridguy
February 20th, 2013, 03:06 PM
There is a how to here regarding an install using UEFI mode.

https://help.ubuntu.com/community/UEFI

Also in this thread , lots of info, regarding windows 8, but same principle as windows 7 if
you are using UEFI.

http://ubuntuforums.org/showthread.php?t=2107873

oldfred
February 20th, 2013, 09:09 PM
When you reinstalled Windows 7, did you install in BIOS/MBR or UEFI/gpt.

If in BIOS mode you will need fixparts as Windows do not correctly convert from gpt to MBR(msdos) partitioning. It removes primary partition table but gpt has a backup (on of its advantages) and Windows leaves backup. Then Linux sees MBR and backup gpt and gets confused.

Only if now MBR.
Fixparts - Repair broken partition tables (not overlapping issues) & delete Stray gpt data from MBR drives
http://ubuntuforums.org/showthread.php?t=1705325
http://www.rodsbooks.com/fixparts/
First backup partition table, use your drive for sdX or sda, sdb etc.
sudo sfdisk -d /dev/sdX > parts.txt

Windows only boots from gpt partitioned drive with UEFI.
Ubuntu will boot from either gpt or MBR with BIOS.
UEFI requires gpt.

flintdk
February 20th, 2013, 11:55 PM
@offgridguy: Yup, I had already read the article on installing Ubuntu in EFI mode. Windows 7 is already installed in EFI mode. The BIOS is set to boot UEFI only (legacy support is not enabled). The 64-bit Ubuntu 12.10 live CD boots nicely with this setup. In the link you recommended there is a section "Identifying if the computer boots the CD in EFI mode" - and yes I see that screen, the CD is booting in EFI mode.

The thread on Windows 8 is indeed interesting - but I haven't attempted using the 'Something else' option yet. I was hoping to find a way to get Ubuntu 12.10 to recognise the existing Windows install and install itself to the free drive space.

@oldfred: I installed Windows 7 in UEFI/gpt (from a UEFI bootable USB Drive)

I didn't realise that fixparts was only for fixing MBR disks when I read about it here, that's not applicable in my case so as the disk is GPT.


So... I could go down the "something else" install option but would prefer to figure out why Ubuntu isn't seeing my existing Windows 7 install.

oldfred
February 21st, 2013, 12:46 AM
If you have installed an do not get a working Windows boot entry then it is this bug. Boot-Repair can fix it.

grub2's os-prober creates wrong style (BIOS) chain boot entry
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1024383
type of entry from Boot-Repair that should work.
'Windows UEFI loader'
Type of entry that does not work:
'Windows ...) (on /dev/sdXY)'
Boot Repair -Also handles LVM, GPT, separate /boot and UEFI dual boot.:
https://help.ubuntu.com/community/Boot-Repair


If not post link to BootInfo report that Boot-Repair can create.

flintdk
February 21st, 2013, 12:36 PM
Hi - nope I've not installed. I'll post a link to the boot information as soon as I can, thanks!

oldfred
February 21st, 2013, 02:45 PM
This was Windows 8, but other than secure boot it should be the same.

Lenovo Z580 laptop
http://ubuntuforums.org/showthread.php?t=2112271