My MBA 2012 with OS X 10.9.4 Mavericks won't boot anymore - it simply freezes after the initial jingle. I already tried resetting NVRAM and SMC, but to no avail. I don't have any time machine backups.However, I still have a disc image of Mavericks sitting on an external hard drive, a USB stick and access to a notebook with Windows 7.I haven't yet found any tutorial on how to create a bootable USB drive on Windows in order to reinstall OS X on my beloved Macbook Air.Any help would be greatly appreciated! According to the first answer here, there's a tool with a free trial called TransMac that can do it. Just make sure the USB drive is formatted with GPT and not MBR.What might be easier, however, is that that model has support for Internet Recovery. If you boot holding Command-R and you have a WiFi connection, it can actually boot into recovery mode without a recovery partition on a drive (or even without a working drive).Having said that, your description of a crash right after the boot chime could signify a more serious hardware problem and you may not be able to boot anything. If you boot holding the option key down, the startup disk selection screen should appear.
![Usb Usb](/uploads/1/2/5/6/125628259/583545259.jpg)
If you have the DMG file of macOS and a USB flash drive of size greater than 16 GB, it’s easy to prepare the Mac OS X bootable USB on a Windows PC. Simply follow the given below instructions to prepare your bootable USB of macOS on a PC. Create macOS Bootable USB on Windows 10.
If it crashes anyways, you may be looking at a hardware problem. I know this question is old but it is still valid. I was never able to write a Mac installer image to my Flash Drive and have it bootable, unless I did it on a Mac. Using Michael D. Dryden's, I was able to use the Diskpart command to clean and prep a GPT partition on a flash drive for an OSX Mavericks install image.I used TransMac on Windows 7 to restore the image file I had to the Flash Drive, it created a bootable Mac image on my flash drive. Someone had reported that the method for using DISKPART did not work, but I have done this twice and it works remarkably well, and it's the only method I could find to create a Mac-Bootable Flash.
I've been trying to post this to confirm that it works for some time, I just hope it helps someone else, because it is a very easy solution.Here are the Diskpart commands used to prep the Flash Drive, just to have them here in case my Link does not work: diskpartDISKPART list disk(Find the disk number) DISKPART select disk x (from result of List Disk)Disk x is now the selected disk. DISKPART cleanDiskPart succeeded in cleaning the disk. DISKPART convert gptDiskPart successfully converted the selected disk to GPT format. DISKPART create partition primaryNote: I use 'Rufus' for all other USB writing and formatting for Windows systems, it's a great app, but I had previously tried to format the drive as GPT using that, as a Fat32 partition. When I tried to inject the image, Transmac told me that the drive was 'write protected'. So basically, the USB drive cannot have any high level formatting, the Windows system should detect the drive as 'not formatted' for this to work, which it will if prepped right with Diskpart.