Using a pretty nifty trick you can reset a forgotten Mac password without a Mac OS X installer CD/DVD. The steps may seem a little intimidating at first but I assure you it’s easy if you follow them exactly, here is exactly how to do this in three stages:
Stage 1) Boot into Single User Mode and remove a setup file
•Restart the Mac holding down the Command+S keys, this will take you into Single User Mode and it’s Terminal interface
•You’ll need to check the filesystem first:
fsck -fy
•Next, you must mount the root drive as writeable so that changes will save:
mount -uw /
•Now, type the following command exactly, followed by the enter key:
rm /var/db/.applesetupdone
•After removing the applesetupdone file, you need to reboot, type ‘reboot’ and hit enter
