No Entry Symbol On Mac? What Does It Mean?
A circle with a line through can happen while booting of macOS and it mean that “Startup Disk” which is generally a hard drive installed in your mac has a macOS but for a possible reason that your mac cant use, reason can be many like corrupted macOS, etc the best option a try by Reinstalling the macOS by recovery option or a USB I always recommended the USB option as it allows you to do multiple troubleshooting and work faster compared to internet recovery.
How to reinstall macOS from macOS Recovery
macOS Recovery makes it easy to reinstall the macOS, For an internet recovery, you must have High-Speed Internet Connection as in the process of recovery the macOS download all the required files from an internet source and having a good speed makes the process easy and fast. Try to avoid it doing on the public internet or through a hotspot of the phone as they are slow and not reliable while means that after downloading the files up to 99% it may stop and you have to do all process again.
1. Startup from macOS Recovery :
To start up from macOS Recovery, turn on your Mac and immediately press and hold [Command + R] or [Option + R] one of the above combinations on your keyboard. Release the keys once you see an Apple logo or a black spinning globe. If there is any Firmware password set you will ask to type. Once that done make sure the wifi is connected.
On the next screen you will see the Utilities window. Select the Reinstall macOS and continue
2. You can do it Full Format of Hard Drive.
If there is any important data you can process installation without a format. In case if you plan to erase fully you can choose disk utility and select your drive and click erase keeping all settings as default.
3. Install macOS
When you are ready to install macOS, Choose reinstall macOS from the utility screen. then click continue and follow the screen which will ask you where you want to install an operating system where you can choose your hard drive which will have a default name as Machantosh HD or MAC HDD and select next.
After the installation, it will ask you for the USER name and password and few settings to implement like your location iCloud account, etc which you can choose/ select accordingly. The very much important part is saving of data if you think you have very much important data in the drive get in touch with any local apple technician as they will back up the data by removing the hard drive before re-installation.
[In case while formatting drive, if it gives you an error or takes a long time to format it can be a possible issue with the hard drive,] for which you can get in touch with Apple Macbook Repair Center or any local technician for further troubleshooting