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Pete
Pete, Computer Engineer
Category: Computer
Satisfied Customers: 18127
Experience:  CISCO certified, Microsoft proficient, computing expert.
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My name is ***** *****, and I want to make a clean El

Customer Question

Customer: Hi. My name is ***** *****, and I want to make a clean El Capitan install. I downloaded the dmg and made a booteable USB drive, but every time I try to boot from the USB I saw a prohibited sign and no errors
JA: Thanks. Can you give me any more details about your issue?
Customer: ask
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Submitted: 2 years ago.
Category: Computer
Customer: replied 2 years ago.
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Customer: replied 2 years ago.
Just a note, it is a Mac related question, not a Microsoft Office...
Expert:  Pete replied 2 years ago.

Hi,

What method did you use to make the bootable USB drive?

You should try DiskMaker X, and see if that works for you.

If you still get the Prohibited message, then:

  1. Try to boot into single user mode and repair the disk drive.
  2. You could download Recovery Disk Assistant, which you can use to repair your hard drive or reinstall OSX.
  3. You could try mounting the MBPR HD in target disk mode on another Mac, and then repair the HD.