MacBook showing 'stop sign' on startup

[ZebraTalent]

Hey everyone,

I'm looking for some help if possible

(Sorry if this is the wrong place to post this, please feel free to point me in the right direction if it is).

So I have a late 2011 MacBook Pro running El Capitan. Yesterday I decided to install Windows on it via Boot Camp. So I loaded up the Boot Camp installer through the Mac OS.

I created a partition and then inserted the Windows 8.1 CD and clicked to start the install process via Boot Camp install assistant.

The Mac restarted and loaded up the windows installer. I installed Windows and everything appeared to be fine (in as much as I was using Windows for the rest of the day once it had installed).

This morning I turn the MacBook on to use the Mac OS as usual, but before the Apple logo appeared I was immediately presented with a 'Stop sign.'

I have attempted a couple of things to remedy this:

• Tried booting in safe mode holding shift key on start up. Didn’t work.

• Tried resetting PRAM holding CMD+option+P+R. Didn’t work.

I then decided to load into Disk Utility using CMD+option+R:

• The Macintosh HD is greyed out and it says the Macintosh HD is not mounted.

• I select Macintosh HD then click ‘Unlock’

• I can then 'Verify Disk', it says ‘The volume Macintosh HD appears to be OK.’

• I then ‘Repair Disk’, says ‘The volume Macintosh HD appears to be OK.’

• Restarted, still get the stop sign

• When I go back into Disk Utility, the Macintosh HD is greyed out again and saying not mounted.
• So I unlock the disk again. I can still verify disk and repair disk and it says it's OK.

• 'Verify disk permissions' and 'Repair disk permissions are greyed out'. It says I can’t click these because the selected disk is not a start up disk.

• When I select the '750.16GB TOSHIBA' drive in the sidebar and click Verify disk, I get an alert that says ‘Storage system verify or repair failed.’ It says this when I click Repair disk as well.

I don't suppose anyone has any thoughts on this do they?

I know the likely answer is probably to format and re-install the Mac OS - in this case, does anyone have any support for how I can install Windows without messing up my Mac HD?

Thank you all very much in advance for any help! It will be greatly appreciated

 

[Brian33]

It might not work, but try holding just the Alt key while it boots, to get the "boot picker" screen. It should come up with a screen with an icon for each bootable partition. I.e., there should be one for macOS and one for Windows.

From your description though, I suspect it will only show the Windows partition. There still may be a way to mark the macOS side as bootable but that goes beyond my knowledge...
[doublepost=1554908057][/doublepost]If you do have to reinstall, you should be able to leave the Windows partition as-is, that is, in a working state. Just make sure you reinstall macOS to the proper partition. You may or may not have to re-format the macOS partition.

 

[ZebraTalent]

It might not work, but try holding just the Alt key while it boots, to get the "boot picker" screen. It should come up with a screen with an icon for each bootable partition. I.e., there should be one for macOS and one for Windows.

From your description though, I suspect it will only show the Windows partition. There still may be a way to mark the macOS side as bootable but that goes beyond my knowledge...
[doublepost=1554908057][/doublepost]If you do have to reinstall, you should be able to leave the Windows partition as-is, that is, in a working state. Just make sure you reinstall macOS to the proper partition. You may or may not have to re-format the macOS partition.

Thanks for your reply Brian, I had tried just holding down the Alt key (sorry forgot to mention this), it does show up the Mac OS partition, but once I select it, I am immediately presented with the prohibitory symbol (the stop sign).

What do you mean when you say that I may or may not have to re-format the macOs partition?

 

[Brian33]

What do you mean when you say that I may or may not have to re-format the macOs partition?

I am thinking you could re-install macOS right "on top of" your existing installation. I think this would re-set the boot-up qualities of the partition, yet would not erase your user accounts' documents, etc. I wouldn't do this without being confident I had a good backup, though, just in case. But it should save you some time.

 

[ZebraTalent]

I am thinking you could re-install macOS right "on top of" your existing installation. I think this would re-set the boot-up qualities of the partition, yet would not erase your user accounts' documents, etc. I wouldn't do this without being confident I had a good backup, though, just in case. But it should save you some time.

Thanks, I did attempt this after I replied to you. So I was running El Capitan, and when I try and select the Install OS option in recovery mode, it says, 'You can't upgrade this version of Mac OS X because a newer version is installed.'

I don't suppose you have any thoughts on this do you? For some reason it looks like it's trying to install Lion.

 

[DeltaMac]

You should be offered El Capitan, if you boot up into your recovery system. That's the correct recovery mode that you should be using now, not the mode you booted (which is Internet recovery mode)
That is booting while holding Command+r --- NOT Command+Option+r which boots the Internet recovery system, which will offer you an older OS X version, and might be the oldest system that your Mac supports. You would only use that if you have no other choice)

 

[Brian33]

Yeah, I think that's right, about Cmd+r vs. Cmd+Option+r. I think the internet recovery mode always offers the macOS the machine originally came with.

If you can't re-install with normal recovery mode for some reason, I guess the next thing I would try is get a copy of El Capitan and make a bootable USB flash drive. Searching should reveal instructions about how to do that.

 

[ZebraTalent]

Thanks guys. So two things.

Just to clarify, you are saying to try booting using the key combination CMD+R?
I just tried this, and it still goes through the internet recovery mode :s

I have also been looking at the bootable USB flash drive option, but I actually can't seem to find a reputable place to download the El Capitan installer, when I try through the App Store, it just tells me I can't download it :s

 

[CoastalOR]

I have also been looking at the bootable USB flash drive option, but I actually can't seem to find a reputable place to download the El Capitan installer, when I try through the App Store, it just tells me I can't download it :s

How are you accessing the App Store to download the El Capitan installer if the 2011 MBP does not boot into MacOS?

 

[ZebraTalent]

How are you accessing the App Store to download the El Capitan installer if the 2011 MBP does not boot into MacOS?

Ah, using my other iMac

 

[DeltaMac]

Internet recovery looks almost identical to the installed recovery system.
BIG difference is that, on boot up, the Internet recovery will show a rotating globe, where the Recovery system will show the normal Apple icon. And, starting the "Reinstall OS X" will show your currently install system, and not the older system.

But, then, if you are sure that you only get Internet recovery, that's another indication that there is something else wrong with your install OS X system --- Internet Recovery does NOT use anything that is installed locally. It's booting to Apple's remote servers.
And - best way forward is to get that El Capitan installer app, then make the bootable USB installer.
You can do that easily using the terminal command on this page...

 

[ZebraTalent]

Internet recovery looks almost identical to the installed recovery system.
BIG difference is that, on boot up, the Internet recovery will show a rotating globe, where the Recovery system will show the normal Apple icon. And, starting the "Reinstall OS X" will show your currently install system, and not the older system.

But, then, if you are sure that you only get Internet recovery, that's another indication that there is something else wrong with your install OS X system --- Internet Recovery does NOT use anything that is installed locally. It's booting to Apple's remote servers.
And - best way forward is to get that El Capitan installer app, then make the bootable USB installer.
You can do that easily using the terminal command on this page...

Yeah it's weird, when I run CMD+R - I get the globe.

When I try CMD+SHIFT+OPT+R - I get the prohibitory sign.

I am currently looking at trying to create an El Capitan installer, but I can't for the life of me work out how to download El Capitan. I'm using a different Mac to try and create the USB installer, this Mac is using Mojave, and the App Store will not let me download El Capitan. It just says 'The request version of Mac OS is not available.'

 

[chown33]

See Step 4 here:
"How to upgrade to OS X El Capitan"
https://support.apple.com/en-us/HT206886

I recommend reviewing the other steps, but the download link is at 4.

That download requires running from High Sierra or earlier. Not Mojave.


Here's another link I have:
https://support.apple.com/en-us/HT204904

cmd-shift-opt-R : Install the OS that came with your Mac, or latest version still avail.

 

[CoastalOR]

Ah, using my other iMac

What year is the other iMac? If it is to new to run El Capitan, then the App Store will not let you download the El Capitan installer app.

What is the macOS running on the other iMac?
[doublepost=1555006496][/doublepost]

Here's another link I have:
https://support.apple.com/en-us/HT204904
cmd-shift-opt-R : Install the OS that came with your Mac, or latest version still avail.

The "cmd-shift-opt-R" only works if the Recovery partition is from Sierra (10.12.4). From the linked Support:
'Command-R is generally recommended, especially if you never installed macOS Sierra 10.12.4 or later."

 

[ZebraTalent]

What year is the other iMac? If it is to new to run El Capitan, then the App Store will not let you download the El Capitan installer app.

What is the macOS running on the other iMac?
[doublepost=1555006496][/doublepost]
The "cmd-shift-opt-R" only works if the Recovery partition is from Sierra (10.12.4). From the linked Support:
'Command-R is generally recommended, especially if you never installed macOS Sierra 10.12.4 or later."

It was a newer Mac using Mojave yeah!
[doublepost=1555053793][/doublepost]So everyone, I just wanted to say thank you so very much for all your help and support! Really do appreciate people taking time out of their day to help me

I figured I would let everyone know how I fixed this in the end, if anyone stumbles across this post in the future.

I basically bit the bullet and just erased the HD, then performed a fresh install of Lion, then upgraded it to El Capitan.

I wish I had just done that from the start rather than wasting time trying to install the OS without erasing first and creating a USB installer haha. It just seemed like it should have been a really simple thing to do, that turned out to be weirdly complicated by the obstacle of El Capitan being really hard to hunt down!

Thanks again anyways everyone