Hi. I cannot install anything on my Macbook Air as I have lost the password that prompts before every installation. I rebooted to recovery disk but nothing happens, a globe just keeps rotating. I know very little about apple devices as I have been a Windows user since last 20 years. I have no idea how many passwords we have on an apple device, and which is this password. Nor do I know how many disks, hard drives are there on my device. And I don't have recovery disk. Nor do we have any Apple Service centers in my country. Thanks for help.