It's going to take awhile for it to load the operating system remotely so it's a good time to get a cup of coffee, have a meal and come back when it's ready. I'm holding down those keys here and in a second you will see it show that we're doing internet recovery mode.

That will put us in the internet recovery mode. To do that we are going to restart and when we restart as soon as we hit this button I'm going to hold down the keys Option, Command, and R. So what we want to do now is enter internet recovery mode which will instead of loading the operating system from your drive will actually load the operating system or a simplified version of it from the internet, from Apple so it will allow us then to clean off the drive and reinstall the system. You don't want sign out of WiFi because to use the internet recovery function, which is how we are going to clean the Mac off, we are going to have to use the WiFi so we can contact Apple and not only load in utilities that will help us clean off this Mac but then reinstall the system clean and fresh. The only thing that you want to keep around is WiFi. You want to make sure you are signed out of everything. For instance, you don't want to have the iMessage system still thinking this machine is something that should be sending messages. Make sure everything's good and you won't have anything hanging around on this machine. If you're using Cloud services like for Microsoft or Adobe make sure you are logged out of that. Go into Mail and make sure they're all gone. You can be signed in for things like Twitter, Facebook, etc. Under internet accounts make sure you've removed all your internet accounts. Go into System Preferences, make sure you've turned off all your iCloud services and you've removed your iCloud account. Look everywhere you can think of and sign out and delete accounts. For instance, look in Messages, look in FaceTime, look in iTunes, look in the App Store.

So the first thing you want to do when doing that is make sure you are signed out of everything.

You want to get all your stuff off there and give them a Mac that's just like new. This may happen if you're trying to resell it or pass it along to somebody else. Video Transcript: Something that you may need to do from time to time is to completely clean off a Mac. Check out Erase and Completely Reset Your Mac at YouTube for closed captioning and more options.

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