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I'm trying to add windows 7 for my new 12.10 grub bootloader.

None of the things worked out; such as .. copying bootx64.efi methods, I'm getting this output:

grub-probe --target=fs_uuid /boot/efi/EFI/Microsoft/Boot/bootmgfw.efi

grub-probe: error: cannot find a GRUB drive for /dev/sda1.  Check your

....... my device map .......

(hd0)   /dev/disk/by-id/ata-WDC_WD6400BPVT-55HXZT3_WD-WXD1EA1MSVR4

....... 40_custom .....

menuentry "Microsoft Windows x86_64 UEFI-GPT" { 
    insmod part_gpt
    insmod fat 
    insmod search_fs_uuid
    insmod chain
    search --fs-uuid --no-floppy --set=root 80BD-E086
    chainloader (${root})/efi/Microsoft/Boot/bootmgfw.efi

When booting to windows 7 give me blank black screen with a cursor blinks for 2 seconds then reboot, I've tried boot-repair too.

I think I'm missing Windows UEFI Bootloader files.

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Please indicate your Boot-Info URL. – LovinBuntu Nov 14 '12 at 8:46

Check your /boot/efi directory tree. Assuming your ESP is mounted there, you should have a file called /boot/efi/EFI/Microsoft/Boot/bootmgfw.efi. (Note that the case can vary after /boot/efi, since that's a FAT filesystem, which is case-insensitive.) If that file is missing, try widening the search on /boot/efi; typing find /boot/efi -iname "*.efi". This will show you all the EFI boot loaders and other programs on the ESP.

If the bootmgfw.efi file is present but is in a strange location, try moving it. If it's not present, you'll need to run Microsoft's recovery tools to get it back. They may tinker with your boot loader boot order, though, necessitating booting a Linux emergency disc and fixing things with efibootmgr.

If bootmgfw.efi is present and is where it should be, try grub-mkconfig -o /boot/grub/grub.cfg. This will generate a fresh GRUB configuration file with your 40_custom entry. (That entry obviates the need to probe for your Windows installation.)

If that fails or if you don't like the result, you can supplement or ditch GRUB. I recommend rEFInd (disclaimer: I maintain it). rEFInd has the advantage of auto-probing for available boot loaders at boot time, so it should auto-detect both Windows and GRUB. Since you're using Ubuntu 12.10, rEFInd can even boot Ubuntu without the help of GRUB, although that requires some extra configuration, as described on rEFInd's Linux booting page.

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