Updated, renamed, and tweaked for El Capitan. OS X Bootable Media Creator 1.25 is here.

I decided to update this handy script to fix some bugs and ensure compatibility with El Capitan.  You can find it on my Downloads page or here.





Here are some instructions from the old tool.  Ignore the old text in the pics.

If you get the error “Mount of outer dmg failed.” you will need to start over.  I was able to get it to work by formatting the flash drive by hand and then re-running the program.


Requirements:   SUPER IMPORTANT

Install OS X Mavericks , Yosemite, or El Capitan – From the App Store –  It is free so go get it.

One 8 GB USB Flash Drive – you could use an external hard drive but why when an 8GB thumb drive is 6 bucks.

Name your flash drive something that does NOT have ANY SPACES!!!  i.e.  flashdrive is acceptable but flash drive will break.

Once you have both of those run my apple script.  The script will ask you to choose your install media, that would be the 8GB flash drive, as well as the location of your Install OS X Mavericks installer.  Below is what the process looks like.

1.  Launch the Applescript.  Click OK after you read the dialog box.

Screen Shot 2013-10-22 at 6.49.50 PM

2.  Next select your 8 GB flash drive.  Mine was called thumb drive.Screen Shot 2013-10-22 at 6.49.53 PM

3.  This screen should validate that you selected the correct drive to create your Mavericks boot disk.  Once you click OK it will format the drive as a GUID bootable disk.  This is absolutely necessary in order to create the proper partitioning scheme that OS X can boot from.  If you use an external drive or a thumb drive that has multiple partitions it will destroy all of those extra partitions, hence my suggestion of a dedicated thumb drive.Screen Shot 2013-10-22 at 6.49.59 PM

4.  Next select your “Install OS X Mavericks” app that you downloaded from the App Store.Screen Shot 2013-10-22 at 6.50.10 PM


5.  Once you click OK the process will begin.  At first nothing will happen but after about 5 to 10 seconds you should see the Terminal Application launch.Screen Shot 2013-10-22 at 6.50.16 PM


6.  You should see a window like the one below.  You need to enter your password in order to run the final process.  The password should be the one you use to log into your computer.Screen Shot 2013-10-22 at 6.51.21 PM

7.  Once you have entered the correct password you should see the process start and something that looks like the following.  The time it takes will very.  On really fast disks it only takes 3 to 5 minutes.  On the thumb drive I used it took closer to 20 to 25 mins.  BE PATIENT!  ;-)Screen Shot 2013-10-22 at 6.51.28 PM

8.  If everything worked correctly you should see this.

Screen Shot 2013-10-22 at 7.03.14 PM





4 thoughts on “Updated, renamed, and tweaked for El Capitan. OS X Bootable Media Creator 1.25 is here.

  1. Carl

    I’m sorry but I can’t run your “script”. Clickin gthe link created some sort of binary called “OS”, so I saved link as… and unzipped the file to find it’s an app. When I run the app it unexpectedly quits. Is this a script or an app?

    1. Christopher Silvertooth Post author

      It is an applescript application. Any screen shots you can link too so I can help.



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