Back in the Partition window, under Volume Information, give your flash drive partition a new name. We went with OS X Installer, since that’s basically what it will be, and next to Format, pick Mac.
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 10 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.
Requirements
To format a drive on a Mac, you’ll need the built-in Disk Utility application. Press Command+Space to open the Spotlight search dialog, type “Disk Utility”, and press “Enter” to launch the app. You can also open a Finder window, select “Applications” in the sidebar, and head to Utilities Disk Utility. How to reinstall OS X on your Mac. Before you begin, make sure your Mac is connected to the Internet. Restart your Mac. Immediately hold down the Command (⌘) and R keys after you hear the startup sound to start up in OS X Recovery. When the Recovery window appears, select Disk Utility then click Continue. Format A Flash Drive For Both Mac OS X And Windows - Duration: 4:20. Cult of Mac 283,145 views. Use a bunch of USB Flash drives in a RAID array. Duration: 6:16.
Before 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.
Create Mac OS X bootable USB installation media
Before you can use TransMac, you 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 10.
Setting up GPT partition
Using Flash Drive On Mac
Use 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:
Type the following command to determine the USB flash drive and press Enter:
Type the following command to select the storage and press Enter:
Quick tip: Theselect disk 1
command as an example, but you have to replace 1 with the number of the flash drive you want to use.Type the following commands to delete everything from the USB thumb drive and press Enter:
Type the following command to convert the drive into a GPT partition and press Enter:
Type the following command to select the new partition and press Enter:
After you complete the steps, the USB flash drive from MBR to GPT format, you can use the steps below to create a bootable USB installation media to install Mac OS X.
Create USB install media
Use these steps to create a bootable media to install Mac OS X:
Download and install a copy of TransMac.
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. No kidding. 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.
If you’re having issues trying to create a bootable media, you can get a USB flash drive that comes with Mac OSX ready to install.
Hi there mlr99,
From what you describe it sounds like you are trying to install Lion on your newly installed HDD replacement but its not showing as a disk when you try to actually install Mac OS X. That indicates to me that the drive has not yet been formatted as Mac OS Extended Journaled, so it is not ready for Lion to install onto it. This section of the following article will help you get that drive erased and formatted properly so you can continue with the installation:
Mac Os Format Usb Drive
- Before you begin, make sure your Mac is connected to the Internet.
- Restart your Mac. Immediately hold down the Command (⌘) and R keys after you hear the startup sound to start up in OS X Recovery.
- When the Recovery window appears, select Disk Utility then click Continue.
- Select the indented volume name of your startup disk from the left side of the Disk Utility window, then click the Erase tab.
- If you want to securely erase the drive, click Security Options. Select an erase method, then click OK.
- From the Format pop-up menu, select Mac OS Extended (Journaled). Type a name for your disk, then click Erase.
- After the drive is erased, close the Disk Utility window.
- If you’re not connected to the Internet, choose a network from the Wi-Fi menu.
- Select the option to Reinstall OS X.
- Click Continue and follow the onscreen instructions to reinstall OS X.
Format Thumb Drive Mac Os X
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Format Usb Flash Drive Mac Os X
Oct 1, 2015 7:32 AM