Good day, I installed Ubuntu 12.04 64 bit on the entire partition on a laptop without an OS (Lenovo G480 i5-3230). Then, I decided to create an NTFS partition to install windows 7 64 bit (using a bootable USB) on it. However, when I want to boot with UEFI turned on in the BIOS, all I can boot is my Ubuntu. When I turn off the UEFI mode in the BIOS, I can boot from the USB but Windows 7 won't install on the NTFS partition. How do I install windows 7 alongside Ubuntu and make them both work?
/dev/sda1 fat32 /boot/efi 94.00 Mib 885.00KiB 93.14 MiB boot
/dev/sda2 ext4 / 361.10 GiB 37.89 GiB 323.21 GiB
/dev/sda4 ntfs 100.67 GiB 3.00 GiB 97.66 GiB
/dev/sda3 linux-swap 3.90 GiB --- ---
unallocated 1.02 MiB --- ---
There are 2 slight "failures" for Windows. ( not failures for Linux ).
1.) windows-installer of Windows 7 only wants ntfs-partitions (you have boot-partition in FAT32 ? )
2.) windows-installer of Windows 7 only wants Windows 7 to bet on first parition (boot-partition) of your harddisk.
Later if you want it, that Windows should be by default in first line of boot-list in grub, you can read this here:
How do I set Windows to boot as the default in the boot loader?
This question already has an answer here:
It looks like you've got a BIOS-mode installation of Windows -- your disk is partitioned using the MBR scheme, not GPT as would be required for an EFI-mode installation; and there's a copy of the Windows boot loader in the MBR of the disk. It looks like you've got a reasonable grub.cfg file in your Linux partition, although I've not studied every last line of it; but it looks like something went wrong with the GRUB setup, since there's no trace of GRUB in the hard disk's MBR.
Chances are the Ubuntu Boot Repair tool will be able to get things working, although I can't promise that. If you run it and have problems, post back, since there are manual procedures that will almost certainly work, too.
it may be caused by many reasons but definitely not Windows 8 because I use both Win8 and Ubuntu 13.04
You may have a bad disk. If so, you need to set /boot as a separate partition(/dev/sda1) and put it at the head of the disk.
You may failed to install grub. if so, type grub-install /dev/sda in terminal in a livecd or try a software called "easybcd" under windows.
If your mbr was overwritten by Windows, you may just try
mount /dev/sda[#] /mnt
grub-install --root-directory=/mnt/ /dev/sda
in livecd. (/dev/sda[#] is where you / directory is)
hope you can solve your problem as soon as possible.