MacBook Pro shows circle with diagonal line and won't boot up

Try command option R being held down at power on time until the gray Apple logo appears. Once recovery mode starts, choose Disk Utility and from the menu, choose Select Startup Disk.

Fixed my problem!

If recovery mode won’t start, try command option SHIFT R which will invoke Internet recovery.

Same thing here, when I tried to update my MacBook ‘11 help!

I got the same problem two days ago when my macbook was installing combo update of high sierra.

I tried to reinstall macOS, but downloading took very long time, within 2-3 hours almost ninety percent download done but the remaining portion looked ceased, waited eight hours to complete. cancelled and repeated couple of times but same output. can u suggest me something?

Hello , i’m having the same issue with my macbook pro . I just updated it and the circle with the slash in the middle appeared . How can i get my macbook back to working again? It is obvious that the update is causing this . Any solutions. PLEASE HELP.

Hey just reinstall the update . And it should start working again. Its gonna take a while but your macbook is gonna start working again.

1 Hit the power button

2 hold command and R down until it shows a screen.

Select reinstall and reinstall it . Make sure you are commected to the internet. Good luck

Hey Kingkem

Please take a thorough look and read the following discussion.

New SSD will not boot internally, only from USB.

https://discussions.apple.com/thread/5661626

First thing first applies.

Very useful!

Good luck

yes i tries 3 different hard drive at first - but my big problem was i was using a external usb hard to clone my other mac hard drive. it gave me error every time i tried to clone it. i just got this computer from eBay - i figure that it only spent $ 200.00 on a 3 ghz 8 core computer and if it was a dude it was not a bad deal, but the supply company said that they check the mac first before they sold it to me - so i decided to by a new hard drive - instead of using one of my 6 old hard drives - now all i get is the folder with a ? mark - that one i know about - thanks for your help.

Hey everybody :) . Just reinstall the update . Start the macbook in safe mode . Power it on and hold down COMMAND + R until a screen its gonna pop up with 4 options. Click on reinstall. Its gonna take a while , make sure you are connected to the internet . Once the installation is done . It should be working fine .

Hi! We tried this and it has been updating for 12 hours with very little progress (like when it started it said it had 1 hour 53 minutes and now it says 1 hour 29 minutes). Is this normal and should we wait it out? Or stop it and try again?

Hey sorry couldnt respond faster . Well same thing happened to me , it got stuck at 25% for a couple of hours . I just restarted the computer and started installing it from the beginning . The second time the installing process took about 1:30 max , but it also depends on the internet speed . Make sure you are connected to the internet . Good luck .

For those having this issue with the new update, this worked for me:

Hold Shift+Command+R while powering on to enter recovery mode (hold until apple logo and loading bar appear)

Click the apple in the toolbar at the top of the screen and then click "select startup disk"

There should be one with the number of the previous operating system you had installed (for me, I believe it was 10.13.1). Make sure it's selected and hit the restart button, and your computer should turn on normally. Hope this helps!

Hi! I was having the same issue with my 2013 MacBook Pro. I re-booted my computer, clicked utility dick, ran first aid and then restored my hard drive. I was then able to go back and reinstall the latest version. Hope that helps!

You just need to reinstall the update . Command + r hold em down while the macbook is turning on . A screen is gonna pop up with 4 options. Just click on reinstall mac os x . Make sure you are connected to internet. Good luck.

Hey i had the same issue mine is late 2011 . Just hold down command & R at same while the macbook turns on. And all you need to do is reinstall the update . Make sure you are connected to the internet otherwise it wont work . It shouldnt take longer than 1:30 hour. Good luck .

Hey try using an ethernet cable . Connecting it straight from the router to the macbook, instead of using wi fi . But it could also be because of the apple servers are extremly busy . Try at different times of the day . Good luck .