Reboot fail after installing El Capitan help!!

I've had the same problem for many months and tried various solutions suggested in this forum and others with no luck. Contacted apple via chat and they denied being aware of the issue and suggested I reinstall OS X

Anyway, I found this solution here which worked for me:

http://apple.stackexchange.com/questions/126288/xcode-5-1-wont-launch-being-upda ted-but-already-installed

1. Show the App Store's Debug menu:

   defaults write com.apple.appstore ShowDebugMenu -bool true

2. Select Reset Application and restart the App Store
3. Log in to the App Store through the Purchases tab.
4. Reboot.

Apologies if someone has already posted this but I don't have time to read the whole thread

Hi @Tsofa and @GSfromNL

You together saved my day.

I put together what I did finally, and try to make it more generic.

I had a MacBookPro15 Retina running on 10.8.5 and then updated to 10.11.2 El Capitan without a clean install because I wanted to keep my Quark9.5.4.1 Install alive (the installers do not run on newer Systems anymore). You can manage that but I tried the in place upgrade after having proper backups.

I had a nice running machine after the upgrade but it fails when having a first reboot after 3 days.

After some booting progress the bar stopped at around 75% and I got a black screen with a white stop sign.

Restarting using a pressed Cmd-S or Cmd-V key combination displayed the boot terminal.

The last line ended with "Still wating for root device" before displaying the Stop Sign.

(I add these details all for people to make it easier to find this)

1. Boot your system into the Recovery System by pressing Alt during boot or R
   (with alt you need to manually select your boot partition. If you have a working partition you maybe can avoid the harder terminal stuff I describe now)
2. Open the Terminal from the Utilities menu at the top
3. We need to start Safari via Terminal to have the browser AND another terminal (you cannot open two Applications in Recovery Mode via the GUI) type (no copy paste at this state, sorry):
   /Applications/Safari.app/Contents/MacOS/Safari
   and hit return
4. Confirm all upcoming error messages and wait for Safari to show up. The process binds to the first terminal and blocks it, that is ok for now.
5. Type the URL of this post into Safari by hand and keep the browser window small but handy for reading and copying.
6. Click again into the Terminal Window
7. Create a new Terminal by typing Cmd-N
8. List all partitions of your system:
   type:
   ls /Volumes/
   and hit return.
9. Note down your boot partitions name if not "Macintosh\ HD" (take care of the spaces and special characters if you use diacritical characters. You need to quote them using the backslash I use or by putting your path into quotes.)
10. We create a list of all key extensions of our system and write them to a text file on your desktop using the following terminal command:
    Enter the indented line by replacing [Macintosh\HD] with your boot partitions name and [userid] with your short username. Recovery Mode cannot use the ~ trick to get the current user as GSfromNL suggested.
    system_profiler SPExtensionsDataType > /Volumes/[Macintosh\ HD]/Users/[userid]/Desktop/kextList.txt
    and hit return (this will take a short while to run). Thanks GSfromNL!
11. You can browse the file using the command and use exactly the same path to the textfile as in the preceeding command (you can use arrow up to to reedit the line or copy from there):
    less /Volumes/[Macintosh\ HD]/Users/[userid]/Desktop/kextList.txt
12. It is cumbersome to find what we need by viewing the file like this but you get an idea how it looks.
13. Now we use grep command to filter the lines of the text and get the context of possible errors :
    grep "Loadable:" /Volumes/[Macintosh\ HD]/Users/[userid]/Desktop/kextList.txt
14. You can now scroll again through the result and see if you find a line containing "Loadable: No"
15. If yes you can now find the possible killer kext file by grepping the context like this:
    grep -C10 "Loadable: No" /Volumes/[Macintosh\ HD]/Users/[userid]/Desktop/kextList.txt
    this will fetch a context of 10 lines before and after the found issue.
16. Note down the found path(s) to the faulty kext files
17. We create safe locations outside the System standard boot lookup path to move the files out of the way and keep them just in case we make a mistake. Type into your terminal:
    mkdir /Volumes/[Macintosh\ HD]/System/Library/Extensions/Unsupported
    and: mkdir /Volumes/[Macintosh\ HD]/Library/Extensions/Unsupported
18. Move each extension you found into the new locations depending on which base path was listed (/Library/... or /System/Library/...) type:
    mv /Volumes/[Macintosh\ HD]/Library/Extensions/[myfaulty.kext] /Volumes/[Macintosh\ HD]/Library/Extensions/Unsupported/
    and / ormv /Volumes/[Macintosh\ HD]/System/Library/Extensions/[myfaulty.kext] /Volumes/[Macintosh\ HD]/System/Library/Extensions/Unsupported/
19. Reboot your system!

I wish you success!

Sorry for the verbose list in detail, but newbees with just finder experience need this, if they want to help themselves.

Remark:

One could simplify the commands using the cd command first and then go on from there. But I avoided it here. My approach is more explicit and helps if you are lost with the other procedures posted before from others.

Tipps:

• Open a third terminal to keep the grep results in focus when you have multiple kill candidates.
• When you type your individual paths in the terminal, try to hit "tab" after each "/" . The terminal can autocomplete your path if the solution ist obvious.
• Try typing tab multiple times to get alternate suggestions that e.g are possible partition or usernames!
• Be lazy: Arrow-Up and down gives access to your command history

I too have this problem. Never had an issue upgrading yearly from OS X Lion 10.7, nor any kind of hardware issue on my Mid-2011 MacBook Air 13".

First installation of El Capitan, was easy and went without any hiccups. It loaded the new El Capitan no problem. It's only after the subsequent reboot/restart/shut down restart, my MacBook just hangs at boot. After the Mac chime, it just shows a white background, with Apple logo, and zero progress bar stuck indefinitely.

At this screen, I've tried:

1. restarting by holding down the power button, tens of times

2. doing a NVRAM reset tens of times

3. entering restore mode (CMD-R) several times to check for errors

4. to restore from an earlier image file of El Capitan from Time Capsule several times

5. to do a clean installation of both Yosemite and El Capitan several times from the restore utility

6. to restore from an earlier image file of Yosemite from Time Capsule ONCE, but it only to have a "prohibited sign" at reboot after completing the restore and restarting automatically

7. successfully using my Mac for an hour or so, after El Capitan has installed and running up, BEFORE i then go to restart/reboot (which then hangs)

7. all the steps (applicable to my case) you've recommended

and...... still same white background with Apple logo and zero progress bar stuck.

I think since public release on the 1st Oct till now, I've done over 10 restores/clean installations. And doing another restore of an image file a day before all these happened, just as I'm typing.

Do you still think it's hardware fault, even though:

- i'm able to complete the new clean installation each time

- i'm able to complete restore an El Capitan image file from Time Machine, and yet use my Mac under El Capitan with no issues after installation/restore for an hour or so, but yet hangs after i proceed to reboot/restart?

Note: After each installation/restore, I start backing up to Time Machine just have an image after each trial.

I appreciate your time and help.

Thanks!

SweeJ

Hi, I have the same issue.

Downloaded ElCap yesterday and installed without any problem. Did look beautiful but got some syncing problems with my iPhone 4S with up to date iOS 9.02 (the same dreaded 'circles' as after the update to iOS8) and hoped a reboot of both devices would fix it.

But, no reboot on my Mac, only the white screen with Apple logo and a stuck progress bar.

Tried to start with 2 different external bootable HD's (a FW and a USB) but the computer does not 'see' this disks. They are working OK, tried them with my wife's Mac, and both HD's do boot.

Also, in recovery mode it does not see the recovery partition.

Only recovery via internet works, El Cap gets re-installed and I'm back in my Mac, everything working.

Tried to reboot again, and the Mac is again stuck with a non-moving progress bar.

Again recovery via internet, and my Mac works again, I'm typing this post with it at the moment.

I'm making a clone with CCC right now, takes a while (> 500GB) to see if this disk will work.

Strange is also that I made a Time Machine backup 3 days ago that I can see on my wife's Mac (still on Yosemite), but my Mac in recovery mode sees only older backups, from july and earlier.

Using my internal SSD in target mode works OK, all my files are there, and I can see the EFI and recovery partitions, but also my wife's Mac is not booting with that disk, the same stuck statusbar...

So, I believe my Mac's hardware is OK, it looks that my 1 month old Samsung EVO SSD could be broken, (some system files somehow repeatedly erased?) but disk utility does not find any problems.

I'm pretty sure when I reboot I have again to do a recovery.

Will try and keep posted...

Hopefully someone has any idea?

My system is a Macbook Pro 15" I7 2.2Ghz, 16GB memory and a Samsung EVO 1Tb SSD.

Logic board was replaced by Apple last month under extended warranty because of a GPU failure...

I'm having the exact same issue as well. I can do a reinstall, and the system works great - but if I dare to do a reboot, it's stuck on the progress bar with 0%.

For whatever reason I'm also unable to start in safe mode. Only way I can bring the system back is to do a recovery and reinstall.

Forgot to write: Also with me Safe Mode not working.

The problem seems, at least to me, not to be faulty hardware, but an ElCap problem that causes some(?) system files to get corrupt while rebooting.

Why does, after reinstalling ElCap via internet, the Mac start up as normal, but will not reboot...???

As I wrote: in target mode another Mac has the same problem with a stuck progress bar.

Disk utility sees no problems at all...

Note: I did not do a clean install (yet).

Wolfman2015: What kind of system and HD/SSD do you use?

You're not alone, I finally had to do a restore to the previous OS. Everything I tried with Apple Tech Support holding my hand failed. I finally restored backwards.

Lost my Parallels/Windows 7 in the process but at least the machine is usable now.

El Capitan = no bueno.

Additional Details: iMac (Mid 2011) stock factory configuration. I upgraded from Yosemite.

This is pretty frustrating. Glad to see that my situation is not unique, but would rather see a resolution/fix from Apple.

Unfortunately, this is the only solution reinstall from USB bootable and not reboot until new updates fix are coming!!! I should remember when apple came with Snow Leopard was kind the same lots of problems, system slow, manu updates and fix lots of incompatibility software we had like 6 months of terrific time we where actually testing the system for them ... I have the feeling that El Capitan is the worse update aver ... the name itself suc*** ... How can they come up with such big GAP leave many working people stuck with a not bootable mac??!??!!? HOWWWWWWWW??

I suggest to keep always a bootable USB each time Apple come with a new big Update.

Gook luck!

For everyone: faulty KEXTS...

I found yesterday evening the same in the developers forum mentioned by Tsofa.

Did not have the time to post or the time to check my Kext's. Will do today and make a bootable USB as well.

But:

Do not use the line mentioned in post following point 6 from Tsofa!

This solution was tailored for a specific user by a Mac-Guru called Max108 (Thanks!) and therefore not suitable for every user.

First look at the Kext's that Terminal will display, copy and paste it in a text editor.

Then look very careful what Kext's you do'nt use or are suspected.

Also: in the line after 6 it says:

cd "/Volumes/Macintosh HD/Library/Extensions/" (and so on...)

Do not put in both quotes and replace the name Macintosh HD with the name of your harddisk or SSD.

Start your Mac keeping CMD+S pressed until you see white text on a black background then release them.

At some point (very soon after boot) your Mac will hang telling you (I'm sorry, you'll have to read it yourself) that something crashed, showing you a backtrace of the problem.

You'll see something like com.somevendor.somesoftware is in the backtrace.

That identifier can help to find what software is causing the problem.

Once you have the kext name you can boot in Recovery, start Terminal and do a

# cd /Volumes/YourHDName/System/Library/Extensions/

# rm -r FaultyKext.kext

# cd ../Caches

# rm com.apple.kext.caches

# nvram -d boot-args

The last step is to clear the nvram.

This steps are to remove a faulty kext only, please don't use them if your problem is not kext related.

I'm sorry I cannot help more than this, mainly because (1) English is not my native language and (2) I can't replicate the issue right now

I had the same problem. El Capitan installed OK, but when I did a reboot, I just got the white screen with the Apple logo, and a progress bar that progressed about 2/3 of the way. After an hour of nothing happening, I shut down my iMac completely. Here is what I did and it worked:

1. Shut your Mac down completely with the power button .

2. Press and hold down the Option key - don't let it go, just keep holding it down.

3. Press your power on button to start up your Mac.

4. In a short while you will see two hard drives. The one on the left is silver in color, and the one on the right is Orange/Yellow which is your recovery drive.

5. Click your mouse only on the silver hard drive icon.

6. It should immediately boot your Mac into El Capitan.

7. If you just turn on with the power button, without holding down the Option key, it will just sit there and nothing will happen as I said in my first paragraph.

I hope it works for you, and I hope Apple fixes this problem soon so it will boot up normally.

Good Luck 🙂

Similar story here,

updated then it restarted the system and my login screen came up (apple encrypted HDD). So far all smooth but after I enter the password the system crashes and starts again. I reset PRAM / SMC no change, and I couldnt even boot in the safe mode. Hardware test result was fine no issues at all. Lucky I could recover from a time machine backup though I still lost my parallels system now forever.... Thanks Apple great Job on this update.... Steve would have fired the whole lot of you on the spot.

Hi GSfromNL,

I reinstalled El Capital 3 times, reset pram, reboot and use the disk utilities to repair disk (o permission repair anymore in El Capitan), try safe boot (not working) and finally your solution, because the first reboot fail after installing.

But when I go to step 4 "Not Signed" nothing happened, no list. So it seems not to be the solution ?

Suppose you have the TXT file open in Texteditor? Press command and F and there is a search field on top. If you put in Not Signed you must see the 'not signed kexts'. Unless there are no unsigned kexts... Maybe you can post the txt file, I will have a look...