С macbook air вышеописанный способ не проходит, невозможно изменить объем оперативной памяти. Остается только нести в сертифицированный сервис...

Как раз работаю там..связывался с сервисниками Apple они говорят , что только плату им отправлять по обмену..а это 70 % ее стоимости... и под гарантию такой случай не попадает ...du_ma_et:

Learn what to do if you no longer remember the firmware password that you've set or if you see a password dialog when you try to select a startup volume on a MacBook Air (Late 2010) and later, MacBook Pro (Early 2011) and later, iMac (Mid 2011) and later, or Mac mini (Mid 2011) computer.

Only Apple retail stores or Apple Authorized Service Providers can unlock these computers protected by a firmware password.

If you cannot remember the firmware password for your Mac, schedule a service appointment with either an Apple Retail Store or an Apple Authorized Service Provider. If you plan to visit an Apple Retail store, please make a reservation at the Genius Bar using http://www.apple.com/retail/geniusbar/ (available in some countries only).

For the MacBook Air (Late 2010) and later, MacBook Pro (Early 2011) and later, iMac (Mid 2011) and later, and Mac mini (Mid 2011):

Use the new Firmware Password Reset scheme:

Start up the computer to the password entry screen by pressing and holding the Option key.
Press the key sequence Shift + Control + Command + Option + S at this screen. A one-time use "Hash" code will appear. The code is case-sensitive, so provide TSPS with the Hash exactly as it appears on the customer's screen.
Shut down the customer's computer.
Contact TSPS via chat. Select Yes for the pre-chat question regarding firmware reset and provide the Hash to the advisor assisting you.
TSPS will provide a signed binary file to be copied to a USB storage device (such as a flash formatted FAT or a USB hard drive with Mac OS Extended with GUID partition table).
Insert the drive into the computer while it is off.
Start up the computer while pressing and holding the Option key. Continue holding the Option key until the boot picker in EFI appears and confirm the password has been removed.
Note: If the computer does not start up without the password prompt after following these steps and while you are holding down the Option key, either the Hash was provided incorrectly to TSPS or the file did not read off the drive successfully. The file may have been read correctly but confirmed it does not belong in the computer. Work with TSPS to troubleshoot these issues if necessary.
This process is completely non-destructive to data or settings on the target computer.

Note: If a customer has multiple computers with this issue, TSPS can handle up to 500 in one file. To escalate multiple computers, follow the steps above with the following additional step:

Provide all the Hash keys in a new-line delimited text file (not RTF, but pure plain text) with no new line at the end. These files can be produced in TextEdit on Mac OS X, or files with multiple entries using vim on the command line.
For example:
V400300C1231MED144431A4F414420DDE5F1
C455300Z555ABJ1118713148F413390ACE341
C891200J18334D1099A3B6DD004E3F1A0122
(No new line after the last entry.)

After you receive the signed binary file from TSPS, use this procedure to reset the EFI firmware password:

Format a Flash drive GUID partition scheme and Mac OS Extended format. Name it Firmware.
Drag the binary file named "SCBO" to your Desktop.
Open Terminal.
Execute this command in Terminal:
cp ~/Desktop/SCBO /Volumes/Firmware/.SCBO
You should get a new line, no errors.
Execute this command in Terminal:
cp ~/Desktop/SCBO /Volumes/Firmware/._SCBO
You should get a new line, no errors.
Eject the Flash drive.
Turn off the customer's computer.
Insert the Flash drive into the customer's computer.
Turn on the customer's computer while pressing and holding the Option key.
You should see the lock symbol for a moment, and then the computer should restart to the Startup Manager.
If you still see a four-digit passcode lock after these steps at startup, reset the NVRAM by holding down Command-Option-P-R while restarting the computer.
The EFI password is now removed.

this worked for me thank you

Как раз работаю там..связывался с сервисниками Apple они говорят , что только плату им отправлять по обмену..а это 70 % ее стоимости... и под гарантию такой случай не попадает ...du_ma_et:

Процедура несложная, посмотри выше на английском я полностью все описал, там не дают дамп биоса на флэшке, там чето типа микропрограммы, она записывается на флэшку, затем аппарат загружается с этой флэшки, чето делает с биосом и как результат пароля нет.
В руки мне саму микропрограмму не давали, все делали сами, но подробно описали процедуру.

Brand new pre-programmed chip
* 100 % verified programming
* Comprehensive technical support
* Fast shipping
(Chip to be soldered on board)
This item is a brand new pre-programmed BIOS EFI firmware chip for the Apple model in the title of this auction item. The bios chip will be programmed with a working EFI firmware released from Apple. This chip has to be soldered on board.
This item can be used for the following purposes:
(1) to fix a corrupt (bricked) EFI firmware bios chip.
(2) to unlock the EFI firmware password (it will NOT unlock the OS password).

Lost Firmware Password

If the Firmware password is lost, follow these steps. This procedure works on both PowerPC and Intel-based Mac computers.
1.Shut down the computer.
2.Gain access to the computer's RAM slots.
3.Add or remove a RAM DIMM to change the total amount of installed RAM. For example:
If the computer has two RAM DIMMs (128 MB DIMM and 64 MB DIMM) for a total of 192 MB of memory, remove the 64 MB DIMM. This changes the total memory of the computer to 128 MB RAM.
If the computer has a single RAM DIMM, you can change the total memory by adding a DIMM of any compatible size.
NOTE: Removing a computer's only DIMM is not an option and will prevent the computer from starting up.
4.Turn on the computer and immediately reset PRAM by holding the Command-Option-P-R key combination. Press the keys until you've heard two successive startup sounds.
5.Open Firmware password protection is now disabled. Shut down the computer and return it to its original RAM configuration.

Эти же действия необходимо проделать если пароль стоит в EFI . Но это возможно только в устройствах со съемной RAM тоесть с MacBook Air вырисовываются крупные проблемы..

very thanks