Problem at login for the first time

Question

I'd bought an macbook air 2013 13" today, i shut on, i answered to all questions to the first time. name password etc..
it reboot, and ask me for login, i put the same names et password.. but it shake at all time.
It is mint ! and it doesn't work.
i tried to make a clean install from a usb bootable disk with Mountain lion 1.8.4 which it recognized in my IMAC and launch ML installation, but
in my air it write EFI BOOT when i hold Alt at boot.. (near macintosh HD & recovery
i'd tested all, clean PRAM. when i click on EFI BOOT, there is this picture ( TS1411_1.gif )
I'll test recovery this night because is too long. but i think it will not work.
Can you help me, before i go Apple for exchange please.
Sorry Sorry for my english.

Answer 1

First, make sure caps lock is not on.
If the user account is associated with an Apple ID, and you know the Apple ID password, then maybe the Apple ID can be used to reset your user account password.
Otherwise*, boot into Recovery mode. When the OS X Utilities screen appears, select
Utilities > Terminal
from the menu bar. In the Terminal window, type this:
res
Press the tab key. The partial command you typed will automatically be completed to this:
resetpassword
Press return. A Reset Password window opens.
Select your boot volume ("Macintosh HD," unless you gave it a different name) if not already selected.
Select your username from the menu labeled Select the user account if not already selected.
Follow the prompts to reset the password. It's safest to choose a password that includes only the characters a-z, A-Z, and 0-9.
Select
Restart
from the Apple menu in the menu bar.
You should now be able to log in with the new password, but your Keychain will be reset (empty.) If you've forgotten the Keychain password (which is ordinarily the same as your login password), there's no way to recover it.