i have a macbook air 13-inch,which i bought from a friend before he left for the us and he forgot to give me his password,how do i operate it since i dont have his tel no in the us, how do i cracked the adm/passwords

http://pondini.org/OSX/Password.html

It is apparent that the actual hardware is password protected in firmware.

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

If you do not have 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).

Hi

There are probably several other things to be thinking about.

Like getting the registration changed from him to you - here is one thread but you need to sort this out if the Mac isn't under your Apple ID.

https://discussions.apple.com/thread/3918561?start=0&tstart=0

He should also have done this.

http://support.apple.com/kb/HT5189

http://reviews.cnet.com/8301-13727_7-20011109-263.html

Cheers

Hello.

try this

1- You have to restart your MBA holding down the Command+S keys, and this will take you into Single User Mode and it’s Terminal interface.

2- Then you have to check the filesystem. to do this you have to type the following command in the terminal interface:

fsck -fy

3- Then you have to mount the root drive with write option enabled so you can apply and save any changes. Type this in the temrinal interface:

mount -uw /

4- And then type this command exactly as you see it here:

rm /var/db/.AppleSetupDone

5- Reboot your MBA by typing this in the terminal interface:

reboot

6- After you reboot, you will be see the “Welcome Wizard” startup screen. Follow the wizard and create a new user account. This new account name must be different from the onewhose password you want to recover.

7- Continue and boot into your Mac OS X with the new account you have just created, this new user account is an Administrator and has administrative access

8- Now that you're logged in, go to System Preferences

9- Click on Users & Groups

10- Click on the Lock icon and use your newly created user name and password if asked. This will allow you to make changes to other user accounts

11- On the user panel select the user account whose password you have forgotten and then click on the Change Password... button.

12- Enter your new password

13- Reboot/restart your MBA and now you can log back in with your old account. If you want you can delete the user account you created following this steps.

Hope this helps.

Good luck