EFI Dual Boot Windows 8.1 and Ubuntu 14.04

Your issue

BootNext: 0009
BootCurrent: 000F
Timeout: 0 seconds
BootOrder: 000F,0008,0009,000A,000B,000C,0007,000D,000E,0001
Boot0001* Windows Boot Manager  HD(3,363800,82000,17b1af25-3a01-4b33-9fa5-e6324bca1b76)File(\EFI\ubuntu\grubx64.efi)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}....................

As you have already found out, you probably have a functional entry for \EFI\ubuntu\grubx64.efi that seems to be labelled as Windows Boot Manager, which can be very confusing.

Possible solution

As I don't know of a method to rename these entries I suggest to remove this entry by running the following efibootmgr command:

efibootmgr -B 0001

Where 0001 is the number of the entry to delete and that should be changed according to current efibootmgr output.

To create a new entry run the folllowing command:

efibootmgr -c -d /dev/sdX -p Y -l \EFI\ubuntu\grubx64.efi -L "Ubuntu"

• /dev/sdX should be changed to the actual device name that contains the Ubuntu partition and the EFI System Partition/ESP (it is recommended to have an ESP for each drive you want to boot from), most likely /dev/sda.
• Y is the partition number of the ESP, most likely 1.

A possible workaround or recommended fallback could be to set up gummiboot.

I post an answer because i have many things to share !

1 - Thanks to @LiveWireBT i have create a new entry (named Ubuntu) with EFI Boot Manager and i can choose it with the Windows boot Manager. But when i choose Ubuntu my computer didn't want to boot on it. It boot on Windows.

2 - After I use easybcd thanks to @user305306 and i see that Windows 8.1 is the "by default" system. So i change the configuration to get this :

I reboot my computer and i see a menu who let my choose the system !!! Weepee ! But when i choose Ubuntu i get an error who said that he could not found grubx64.efi. I will post the picture soon !

EDIT : This is the error i get :

In english : The app or system could not be charged because the file is missing or contain errors.