Getting Prohibitory Sign on startup - But not harddrive

Discussion in 'OS X Yosemite (10.10)' started by sgmassey, Jan 10, 2015.

  1. sgmassey macrumors newbie

    Jan 10, 2015
    The prohibitory sign appeared when I started up my macbook pro. I read through the various options listed on this forum and none of them fixed the problem. So I assumed that it was my hard drive or a corrupt operating system. I reinstalled OS X. Still had the problem. Finally, I swapped out my old hard drive with a new hard drive. Still had the problem!! When I tried my old hard drive in my spouse's macbook pro (same model) it booted up just fine! When I but his hard drive (which was working fine) into my macbook pro, I got the prohibitory sign. So I'm assuming it is not my hard drive but some other hardware issue in my macbook pro. Does anyone have any insights into what that hardware issue might be? Thanks!!
  2. user1690 macrumors regular


    Feb 13, 2011
    Huh, that's odd. I always thought the prohibitory sign meant that the operating system wasn't compatible with the system trying to boot it.

    Try this: Whilst turning on the system hold the COMMAND and V keys, the system *should* briefly boot verbose and then halt at the point where the prohibitory icon would usually appear. You should get some sort of error/information that way :)

    Good Luck! :D
  3. hallux macrumors 68030


    Apr 25, 2012
    What year MBP? Many 2010/2011 13" MBP's have been exhibiting issues with the HDD CABLE. You could try swapping the cable between computers and see if the issue follows the cable.
  4. sgmassey thread starter macrumors newbie

    Jan 10, 2015
    That sounds like a promising lead... It's a mid 2009 13" MBP. Thanks!

Share This Page