
If you’re still using a Mac OS X the time will come when your computer won’t boot, or a problem may arise where you can’t take control of the device, and booting from an OS X installation media will be required.This is why it’s recommended that you make a Mac OS X bootable USB when your Mac is in working conditions. However, if you find yourself on a scenario where your device (iMac, MacBook Pro, Air, Mac Pro or Mini) is not responding and you happen to have a Windows device, then you can still be able to make a USB bootable installation media for your Mac OS X to reinstall the operating system using the Recovery Assistant.These instructions will also work for Windows users, who are running Mac OS X on a virtual machine and need to upgrade to the latest version.
For instance, to OS X Yosemite. Things to know before proceedingBefore you dive into this guide, you’ll need a few things:. A broken Mac computer with Mac OS X. A trial copy of the TransMac software. One high quality USB flash drive with 16GB of storage. A copy of Apple’s macOS (DMG file).Now that you have all the necessary ingredients, you’re ready to make a Mac OS X bootable USB using the DMG file of the operating system with the steps below.
You need a USB2 drive with an OS X system installed (I am using 10.4.3, though any I think will. A Panther install CD clone. Windows or linux on it just to try to install os x on it but i cant get it to boot to the usb.
How to create Mac OS X bootable USB installation mediaBefore you can use TransMac, you may first need to partition your USB flash drive with a GPT partition, as a normal MBR partition may not work. To do this, you’ll need to use the Diskpart command-line utility on Windows. Setting up GPT partitionUse these steps to set up a USB drive with a GPT partition:.Open Start on Windows 10.Search for Command Prompt, right-click the top result and select the Run as Administrator option.Type the following command to open Diskpart and press Enter: diskpart. Quick note: TransMac is a paid software, but it has a 15-day trial solution, that give us more than enough time to move the DMG files to the USB drive from Windows. (If you want to support the developer, you can purchase the full version.).Insert the USB drive that you’ll use to fix your installation of OS X.
(Remember that all the data in the USB will be erased. Make sure you take off any important documents.).Right-click the TransMac software icon and Run as administrator.
(You’ll be prompted to Enter Key or Run, because we’ll be using it once, click the Run option.).On the left pane, you’ll see all the Windows PC drives listed, right-click the USB drive that you’re intending to use to reinstall Apple’s OS X and select the Restore with Disk Image option.In the warning dialog box, click the Yes button.Use the Restore Disk Image to Drive dialog box to browse for the DMG file with the installation files for Mac OS X Yosemite in this case, and click the OK button to create a bootable USB of the operating system.Now, you’ll have to wait a long time. It could take one or two hours to complete the process depending on your computer and other variables.Once your bootable USB installation media is ready, remove it and insert it into your Mac, power it on, holding down the Option key, and select the USB you just created to reinstall Mac OS X.
Is it time to sell or give away your old Mac? Or do you just want a fresh start to clean up your machine? Here’s how to securely delete all of your files, then install a fresh version of macOS.If you’re selling or giving away your computer, this is the only way to make sure whoever ends up with your Mac can’t access to your files, and won’t have to deal with any modifications you’ve made to macOS over the years. Don’t just delete your user profile and call it a day—you’ll want to completely wipe it.Before you start, make sure you transfer any files you want to keep to a new computer or external drive. Even if you don’t intend on wiping your drive, it’s a good idea to back up before re-installing your operating system. Step One: Boot From Recovery Mode, or an InstallerRELATED:is a treasure trove of useful tools, and it’s the easiest way to wipe your computer and start from scratch. Shut down your Mac, turn it on while holding down Command+R. Your Mac will boot into the recovery partition.If you’re using an older Mac (from 2010 or earlier), there’s a chance that you can’t use Recovery Mode.
On those devices, hold “Option” while turning your computer on, then select the recovery partition instead.If neither of these options work, don’t panic! You’ve got a couple of options yet. You can: hold Command+Shift+R while turning on your Mac and it will download the Recovery features for you. Failing that, you can, and boot from that by holding “Option” while turning on your Mac.Once you’ve managed to open up the Recovery Mode in some fashion, we can move on to wiping your drive securely.
Step Two: Securely Wipe Your Hard Drive (Optional)If you want to re-install your operating system, but leave your files in place, you can skip this step. Your user accounts and files will stay exactly where they are—only your operating system will be overwritten. We recommend backing up files before you do this, just in case, but otherwise you’re ready for step three.If you want a truly clean installation, however, you need to first wipe your hard drive.
We’ve shown you, and doing so in Recovery Mode isn’t really different from doing so within macOS. To get started, click the Disk Utility option.Depending on how you started Recovery Mode, you may be presented with the option to start Disk Utility right away, as seen above. If not you can find Disk Utility in the menu bar: click Utilities then Disk Utility.You’ll now see your list of hard drives. Click your primary drive, then click “Erase”If you’re wiping a mechanical drive, click “Security Options” in the window that pops up.

(If your Mac has a solid state drive, you can skip this part:. You still need to wipe the drive, however, or your files will remain in place, so skip to the end of this step to do so.)Now move the dial up, to randomly write data over your entire drive., but if you’re paranoid you can also wipe it three or five times.RELATED:Click “OK” once you’ve decided, but remember: if your Mac has a solid state drive, you do not need to use these options. Just give your drive a name (I recommend “Macintosh HD”, just for consistency’s sake), then click “Erase” to start the overwriting process.If you opted to wipe your drive securely, this might take a while—30 minutes to an hour is not unreasonable for one pass. If you choose three or five passes, you might want to leave this running overnight. Step Three: Reinstall macOSWith your information wipe complete, you are now ready to reinstall macOS. If you booted from a functioning recovery partition, click the “Reinstall macOS” button.
The installation process will begin.If you booted from an USB disk, click “Continue” to advance to the installer.You’ll be asked which hard drive you want to install to. Choose the Macintosh HD you named earlier.Just like that, macOS will begin installing.This might take a while.
Eventually your Mac will restart and ask you to create an account. If you’re giving your Mac away, or selling it, I recommend that you simply shut down at this point and let whoever you’re giving your Mac to create their own account.
After all, it’s theirs now. Otherwise, enjoy your now-fresh Mac!