Soon after, an OS X menu bar will pop up along with an OS X Utilities window. Right after you hit restart, press the Command key and R key together and don’t leave them until you see the Apple logo. Step 3: Immediately Press the Command and R keys in unison Pay the most attention here because if you miss something out at this step, consider it gone forever! Then take a deep breath and restart the machine. Once you are satisfied that you have backed up all necessary items, recheck them. Save any setup files that you already have so that you don’t have to re-download them. Also, make a list of all installed applications so that you can download their setups and re-install them after the formatting is complete. You can save all important files through Time Machine or some OS X clone utility. Delete all old, unwanted and unused files that are eating up disk space unnecessarily and save the remaining ones. This also acts as a perfect opportunity to clean up your disk. This is the most important thing to do before you start the reformat process. Step 1: Create a backup of all your files How to Reinstall / Reformat Mac OS X without Recovery Disk or DVD Drive Here’s a step-wise process of how you can reformat your Mac OS X without a recovery DVD for manual installation of OS X Yosemite 10.10, OS X Mavericks 10.9, OS X Mountain Lion 10.8 and so on.

Worry not! Thankfully, Apple thought of this scenario before-hand and created a utility through which your Mac can be good as new again. And since you don’t have it, you land in a scoop! Now, when you reach a situation where you want to reformat the machine at home, the question of having a DVD arises. Though there are ways to boost up its pace but finding out the causes one by one and eliminating them is more time consuming than reformatting. Also, sooner or later, you will want to reformat the Mac, be it because of an OS crash or because your machine has become too sluggish to work on. Practically speaking, taking the machine to a service center is both inconvenient and costly.

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