Last night I decided to install the requested update to Mojave (I think). Since installing I have only a grey screen with a "no entry" sign on my mid-2011 Macbook Air.
I have tried restarting in Safe mode but it didn't work: holding down shift key during restart.
HELP!! Please.....!
MacBook Air 13", macOS 10.13
Does holding alt key at startup show any boot drives?
If not...
To start up from macOS Recovery, turn on your Mac and immediately press and hold one of the following combinations on your keyboard. Command-R is generally recommended, especially if you never installed macOS Sierra 10.12.4 or later.
Command (⌘)-R
Install the latest macOS that was installed on your Mac.
Option-⌘-R
Upgrade to the latest macOS compatible with your Mac.
Shift-Option-⌘-R
Install the macOS that came with your Mac, or the closest version still available.
Does holding alt key at startup show any boot drives?
If not...
To start up from macOS Recovery, turn on your Mac and immediately press and hold one of the following combinations on your keyboard. Command-R is generally recommended, especially if you never installed macOS Sierra 10.12.4 or later.
Command (⌘)-R
Install the latest macOS that was installed on your Mac.
Option-⌘-R
Upgrade to the latest macOS compatible with your Mac.
Shift-Option-⌘-R
Install the macOS that came with your Mac, or the closest version still available.
About the screens your Mac displays as it starts up - Apple Support
"A circle with a line or slash through it means that the selected startup disk contains a Mac operating system, but it's not a macOS that your Mac can use. You should reinstall macOS on that disk."
So you have another Mac you can use or borrow?
You could boot your Mac in Target Disk Mode and access it from the other Mac. From there, you could move enough files off of your Mac to give you the space needed to reinstall.
This solution worked: Command+Option+R. However, it says that my system doesn't have enough memory for the High Sierra re-install: I need an additional 2.11Gb to re-install.
Is my only option to wipe it clean and start from scratch? I hope there is another way.
Appreciate your help!
If Barney's great tip doesn't turn out, a 2nd option would be to install to an external drive & boot from that to clean up the internal drive.
Third option is a bit more risky & complicated, so will wait on that to see if needed.
"No Entry" sign on reboot after installing Mojave update from High Sierra.
