Tmmcm

Q: Prohibitory sign on startup with OS X El Capitan

After installing OS X El Capitan, sometimes when I restart my computer I get a prohibitory sign after startup. I recently upgraded my current SSD with an OWC SSD about 6 months ago. I have never had this issue before. I have tried booting with CMD + R and repairing my SSD which does so successfully but that doesn't seem to help. The only thing that does work is to boot with CMD + R and reinstall my OS. Any help to a permanent fix would be greatly appreciated. This *****!

MacBook Pro with Retina display, OS X El Capitan (10.11)

Posted on Oct 4, 2015 7:13 PM

Close

Q: Prohibitory sign on startup with OS X El Capitan

  • All replies
  • Helpful answers

  • by mario49,

    mario49 mario49 Oct 5, 2015 7:01 AM in response to Tmmcm
    Community Specialists
    Oct 5, 2015 7:01 AM in response to Tmmcm

    Hello Tmmcm,

     

    After reviewing your post, it sounds like the computer will not boot past a prohibitory sign. I would recommend that you read these articles, they may be helpful in troubleshooting your issue.

     

    About the screens you see when your Mac starts up - Apple Support

    When you see a circle with a slash symbol instead of the Apple logo, it means your Mac couldn't find a valid System Folder to start up from.

    If you're using your Mac at a school or business, it might be trying to start from the wrong version of OS X. Contact your IT department for more help. 

    If this is your personal Mac, try reinstalling OS X by using OS X Recovery.

    If may be having a hard time finding the boot drive to start from. 

    How to choose a startup disk on your Mac - Apple Support

    Use these steps to choose a startup disk with Startup Manager:

    1. Turn on or restart your Mac.
    2. Immediately press and hold the Option key. After a few seconds, the Startup Manager appears. If you don't see the volume you want to use, wait a few moments for Startup Manager to finish scanning connected drives.
    3. Use your mouse or trackpad, or left and right arrow keys to select the volume you want to use.
    4. Double-click or press the Return key to start up your Mac from the volume you selected.

    Thanks for using Apple Support Communities.
    Have a nice day

  • by Tmmcm,

    Tmmcm Tmmcm Oct 5, 2015 7:29 AM in response to mario49
    Level 1 (1 points)
    Oct 5, 2015 7:29 AM in response to mario49

    I Tried all of the options above and the only one that works is to reinstall the OS with OS X Recovery. This lasts for about 12 hours and when I shut my Mac down it will boot with a prohibitory sign again and I have to reinstall the OS X.

  • by Tmmcm,

    Tmmcm Tmmcm Oct 6, 2015 7:25 AM in response to Tmmcm
    Level 1 (1 points)
    Oct 6, 2015 7:25 AM in response to Tmmcm

    The solution that has worked for me on my MBP, was to do a Time Machine backup from when I was running OS X Yosemite and not OS X El Capitan. I will update if this is not the correct solution, but for now OS X El Capitan will not run on my MBP.

  • by Marcoach,

    Marcoach Marcoach Oct 19, 2015 5:06 AM in response to Tmmcm
    Level 1 (0 points)
    Oct 19, 2015 5:06 AM in response to Tmmcm

    The same as TMMcM was for me.

    1- Tryed to install on Yosemite and got problem on installation process.

    2- tryed to install fresh OSX El capitan after format , then migrated data from Time machine and got the same as point 1

    3 - Tryed a new OS X installation with, again, blank disk, then  installed some of my previous application ( parallels, final cut, Office 2011 , etc ( all buyed apps ) ) and after one week got the prohibition sign.

    4 - restored last el capitan back-up from time machine ad got prohibition sign after reboot.

    in both point 3 and 4 I noticed a very slow boot up ! Very very slow !

    5 - finallly a restored the last yosemite backup and , fortunately it boot me up again with out any problem !

     

    For more info : I upgraded my mechanic 7200 rpm HD with samsung SDD one year ago.

     

    Probably El Capitan does not work with my MBP or probably with some software I have !!!

  • by Richard Young,

    Richard Young Richard Young Oct 25, 2015 7:12 AM in response to Tmmcm
    Level 1 (6 points)
    Oct 25, 2015 7:12 AM in response to Tmmcm

    Hi, I got the same problem on my MacBook Pro (Retina, 15-inch, Early 2013).

    Just after upgrading to El Capitan 10.11, I do a backup with CCC on an external disk. I reboot on the backup disk to activate FileVault on it. After when I reboot on the internal disk, I got this problems for the first time . After many reboot, I decided to reboot on the backup and restore the internal disk from it. But the backup disk have the problem too . Booting with previous backup (Yosemite) without problems, Both disks (internal and backup) mount ok, and have no problems detected by Disk Utility. Reinstall El Capitan and migrate all stuff from the backup... got the problem again . Reinstall El Capitan, migrate only my user account, boot fine. Upgrading this disk with current version of applications and at ont time when I reboot, the problem happen again . Reinstall again, no migration, update to 10.11.1, upgrade all applications (rebooting between each installation)... Got the problems just after installing 3DConnection (3dxwaremac).

    Coincidence or not??? Retry again but installing latest version of 3dxwaremac, i did'nt get the problem anymore

  • by Richard Young,

    Richard Young Richard Young Oct 27, 2015 1:30 AM in response to Richard Young
    Level 1 (6 points)
    Oct 27, 2015 1:30 AM in response to Richard Young

    I got problem: I was unable to connect to other mac by file sharing. I find no solutions for this.

    So I decided to use CCC to restore El Capitan from another machine to this one. And after I migrate users from my backup.

    Everything seems to work fine now. I have no idea why El Capitan have more problem on this machine than my others???

  • by sjstark,

    sjstark sjstark Oct 30, 2015 11:45 AM in response to Tmmcm
    Level 1 (4 points)
    Desktops
    Oct 30, 2015 11:45 AM in response to Tmmcm

    I’ve got the same problem on my 5.1 Unibody MBP. OSX can be reinstalled runs just fine until the next reboot, were I get prompted the prohibited sign again. I found this approach Re: Reboot fail after installing El Capitan help!! seems promising, will try it now.

  • by Richard Young,

    Richard Young Richard Young Dec 10, 2015 4:39 AM in response to Richard Young
    Level 1 (6 points)
    Dec 10, 2015 4:39 AM in response to Richard Young

    Yesterday I upgraded to 10.11.2, and again, I got the Prohibitory sign again

    This machine is a MacBook Pro (Retina, 15-inch, Early 2013).

    My 2 other Mac [MacBook Pro (17-inch, Early 2011), MacBook Pro (17-inch, 2.4GHZ)] upgraded fine.

    All machines have filevault activated.

     

    Tryed to upgrade a clone of 15" OS on my 17" and I got the Prohibitory sign too. I cloned the OS of my 17" on the 15" and it run fine.

    Seem to be related to the 15" OS, but this OS was already a clone of my 17" OS.

    I conclude that the MacBook 15" modify it's OS in such way that 10.11.x cannot be upgraded. Very strange

  • by Luis Sequeira1,

    Luis Sequeira1 Luis Sequeira1 Dec 10, 2015 6:04 AM in response to Richard Young
    Level 6 (11,889 points)
    Dec 10, 2015 6:04 AM in response to Richard Young

    Tryed to upgrade a clone of 15" OS on my 17" and I got the Prohibitory sign too. I cloned the OS of my 17" on the 15" and it run fine.

     

     

    The way I understand it, it has nothing to do with the mac model, but with something in your previous installation on the 15" - which failed to update regardless of where you used it.

    I bet that if you had tried the other way around, it would have worked - i.e. the system you had on the 17" before updating would *also* have updated successfullt on the 15", and be identical to whar you have now. In other words, 'update on the 17", then clone to the 15"' would be the same as 'clone from the 17" to the 15", and then update'.

  • by Richard Young,

    Richard Young Richard Young Dec 10, 2015 8:28 AM in response to Luis Sequeira1
    Level 1 (6 points)
    Dec 10, 2015 8:28 AM in response to Luis Sequeira1

    I agree with you on the possibility that the machine isn't faulty. After all thousand of people must have the same machine and no problem at all.

    But this machine event with a clean install of 10.11.0. Got the prohibitory symbol after upgrade to 10.11.1.

    Another problem specific to this machine, when I was on Yosemite, was impossibility to make Xcode 6 to run (Other Xcode versions worked). The unique way to make it work have been to start the disk of this machine on my 17", starting Xcode 6 and after Xcode 6 worked fine.

    Look like something on this machine OS wasn't correctly initialized until another MacBook run this OS and by the way finishing some initializations.

  • by Luis Sequeira1,

    Luis Sequeira1 Luis Sequeira1 Dec 10, 2015 8:59 AM in response to Richard Young
    Level 6 (11,889 points)
    Dec 10, 2015 8:59 AM in response to Richard Young

    This appears to be related to your machine rather than the disk containing the OS itself - so things work when using its disk from another mac.

    This suggests something else which is specific to your mac - hence I suggest you try the two things below:

     

    --- Reset NVRAM - hold down the keys Command, Option, P and R until you hear the chime sound some four or five times.

    (NVRAM stands for "NonVolatile RAM", traditionally known as PRAM, for "Parameter RAM", that is where the keys P and R in the above combination come)

     

    --- Also, for good measure, you might also reset the power management system

    See here how to: Resetting the System Management Controller (SMC) on your Mac - Apple Support

  • by Richard Young,

    Richard Young Richard Young Dec 11, 2015 4:48 AM in response to Luis Sequeira1
    Level 1 (6 points)
    Dec 11, 2015 4:48 AM in response to Luis Sequeira1

    Thanks for trying to help me. Very kind.

    I tryed it many times (NVRAM and SMC reset) getting no effects. I even give a try to Apple Hardware Test. It reports nothing.

    For now, replacing the OS by cloning the 17" one seem to works fine... Until the next update of El Capitan.

    Have a nice day

  • by Tmmcm,

    Tmmcm Tmmcm Dec 17, 2015 3:05 PM in response to Richard Young
    Level 1 (1 points)
    Dec 17, 2015 3:05 PM in response to Richard Young

    This seemed to fix my problem. I deleted all 3d plist files from my library under preferences. For finder use Go on the menu bar then Library then Preferences... deleted all 3d plist files and reinstalled El Capitan! Working great for 3 days now. Thank you!