13.10 installer doesn't see Win7

[Dragon2012]

Hi everyone.
I have Windows 7 Professional x64 installed on my Lenovo Y580. I downloaded a ubuntu-13.10-desktop-i386 iso file and booted it from USB drive. I wanted to install Ubuntu next to my operating system, but it doesn't see Win7 installed on my hard drive. I get the info:

This computer has installed operating system MS-DOS 5.x/6.x/Win 3.1.(...)
Install Ubuntu next to MS-DOS 5.x/6.x/Win3.1
I'm afraid such installation would destroy my boot and I will no longer be able to choose Win7 to boot.
I would appreciate any suggestions.

[Mark Phelps]

I'm afraid such installation would destroy my boot and I will no longer be able to choose Win7 to boot.

ALWAYS better to be safe, than to be sorry ...

A good start would be to see what partitions are on the hard drive. To do this, open a terminal and enter "sudo fdisk -lu" (that's a lowercase L, not a one).

[Dragon2012]

Generaly I have two hard drives - one is ADATA 64GB and is SSD, I have Win7 installed on it. The other one is 1TB divided into two partitions. On the first partition I'd like to install Ubuntu.
Here you have the output of "sudo fdisk -lu" (from Ubuntu live USB booted):
http://i.imgur.com/BE2yYzQl.png (http://imgur.com/BE2yYzQ)

[mastablasta]

you can mark text in terminal and copy it and then paste it here.

you need to delete partition where you will install ubuntu (it should be free disk space). furhtermore you have GPT partition table. and if you have EFI see this: https://help.ubuntu.com/community/InstallUbuntu11.10OnLenovoEFI/GPT/WLAN/Power/BIOS

finnaly you will need to put grub on sda.

you could maybe try manual parittioning. you need to at least create / (choose ext4 as file system) and /swap (file system here is swap). when asked where the grub should go choose sda.

[Mark Phelps]

You can't install Ubuntu to an existing NTFS partition; instead, you have to install it to a Linux filesystem partition.

What I would recommend is the following:
1) Download and install the Minitool Partition Wizard in MS Windows.
2) Run Minitool and do the following:
2a) Shrink the second partition on the 1TB drive by 30GB and move it to the right
2b) Move the first partition on the 1TB drive to the right -- leaving 30GB of unallocated space to the left
3) Shutdown the PC and disconnect the SSD -- this is to prevent accidentally writing GRUB to the SSD and corrupting Win7 boot in the process
4) Boot from the Ubuntu install media and using "something else", install it to the 30GB unallocated space
5) Shutdown and reconnect the SSD
6) Reboot -- but be sure to boot from the 1TB HDD
7) Open a terminal and enter "sudo update-grub". This will regenerate the GRUB config file and add an entry for Win7.

When you then reboot, you should get a GRUB menu with entries for Ubuntu and Win7.

[oldfred]

Best not to mix UEFI Window and BIOS Ubuntu although you can. If you do mix them then you only can dual boot from UEFI/BIOS menu not from grub2's menu.
UEFI & BIOS are not compatible and once you start to boot in one mode you cannot switch. So from a grub menu if booted in BIOS will not have a working chain entry to UEFI Windows.

If large drive is MBR(msdos) then you only can install in BIOS boot mode.
How you boot installer is how it installs and if you force a UEFI install it may erase MBR partitioning. Best to have really good backups.

You also may be able to convert MBR to gpt.
Converting from MBR to gpt:
http://ubuntuforums.org/showthread.php?t=1454252
Windows convert from gpt to MBR. Besure to have good backups - srs5694
http://ubuntuforums.org/showthread.php?t=1718966
Use parted or gparted to remove gpt if no data to save:
http://ubuntuforums.org/showthread.php?t=1719851&page=2 post #20
http://www.sevenforums.com/tutorials/26203-convert-gpt-disk-mbr-disk.html

[Dragon2012]

Mark Phelps (http://ubuntuforums.org/member.php?u=311399), I did like you said. After disconnecting the SSD I installed Ubuntu on the unallocated space creating 34GB / ext4 file system and 500MB /swap. After reboot the computer doesn't see this just installed Ubuntu... I mean that I connected my SSD again and now when I press F12 while turning the laptop on I have BOOT menu with options:
Windows Boot Manager (ADATA SX300)
Internal HDD: ADATA SX300
SATA HDD: ST1000LM024 HN-M101MBB
SATA ODD: HL-DT-ST DVDRAM GT50N
Network Boot: Atheros Boot Agent
ADATA is my SSD. So when I choose SATA HDD or SATA ODD option, I get the message (in both cases):
Check cable connection!
PXE-M0F: Exiting Intel PXE ROM.
No bootable device - insert boot disc and press any key.
Where is this Ubuntu which I just installed?!

EDIT:
OK, I did this one more time and Ubuntu is installed OK. I connected the SSD and when I choose to boot from 1GD HDD, I have a GRUB. I logged on Ubuntu and typed "sudo update-grub", here's the outcome:
dawid@dawid-Lenovo-IdeaPad-Y580:~$ sudo update-grub
[sudo] password for dawid:
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-3.11.0-15-generic
Found initrd image: /boot/initrd.img-3.11.0-15-generic
Found memtest86+ image: /boot/memtest86+.bin
Found MS-DOS 5.x/6.x/Win3.1 on /dev/sdb2
done
dawid@dawid-Lenovo-IdeaPad-Y580:~$

So GRUB does not see Windows 7.

EDIT2:
I just used this -> https://help.ubuntu.com/community/Boot-Repair and GRUB is repaired now, sees both Ubuntu and Win7 :). Thanks for your help!