Problems and error messages while booting the Mac

If the Mac no longer boots properly and displays an unfamiliar icon (instead of the Apple logo), then it's too late to google. Which problems and error messages the individual symbols indicate when booting the Mac, you can read here in advance - or see if you are looking for a solution without the Mac, but via iPhone or iPad;) Im Below you will find the background to the question mark, the completely black or gray screen, the rotating globe, the lock symbol, the USB, Thunderbolt and FireWire symbols and other indicators of boot problems on the Mac.

What problems and error messages when booting the Mac do each icon indicate? What do the globe, question mark, warning and prohibition symbol, USB, Thunderbolt and FireWire symbol mean? And why do you have to enter a PIN? Here you get the answer to your question!

What problems and error messages when booting the Mac do each icon indicate? What do the globe, question mark, warning and prohibition symbol, USB, Thunderbolt and FireWire symbol mean? And why do you have to enter a PIN? Here you get the answer to your question!

The Apple logo (usually with a progress bar) indicates that a local hard drive installed in the computer was found to start the Mac. Since this procedure is the standard, the apple, the loading bar and / or a loading circle should always be visible if there are no problems booting the Mac. If the Apple Mac cannot connect to a local startup volume, it will search for a network startup volume. When updating macOS or reinstalling the operating system, the Apple logo and the loading bar may be displayed for a long time.

Blank screen (black, gray, blue, etc.)

If a black screen, greyscreen, blue screen or any other monochrome screen is displayed when the Mac starts, this is not abnormal. When starting macOS, during an update or a new installation, such a display, the desktop background or the like can be displayed again and again. You should only check whether the monitor is switched on or correctly connected if the screen remains permanently black and does not alternate with the Apple logo or is detached from the login screen after a while.

A missing image can of course also indicate a defective graphics card / a faulty GPU chip or a broken graphics unit in the Apple SoC. If a replacement monitor, a different cable or other display tricks don't help, then you should have your Mac checked for a graphic error. That works for example at Sadaghian in Hamburg. Information on the company's unique service can be found with this link. If you want to help yourself first, the Apple support document will help you HT210905 further - with both Intel and Apple Silicon Macs.

Login window

The login window shows that the Mac has successfully booted and you can now log into your user account. Entering the password also means unlocking the memory when using "FileVault". What FileVault is, when it protects the files on the hard drive and what else you should know about it, you can find out in this guide on the topic: FileVault - encrypt hard drive on Mac. You can find more articles and instructions on FileVault using the search function here in the blog.

Rotating globe

If the Apple computer does not access a local storage medium for booting, but rather a network-based startup volume, the rotating globe (with loading bar) is displayed. The symbol can also indicate a macOS restore that is being carried out over the Internet - for example when you start the Mac a corresponding key combination hold down. During this start-up and, above all, during the recovery process, a charging circle can also be displayed and the charging display can be alternated with a blank screen.

Globe with warning notice (triangle with exclamation mark)

If a fixed globe is displayed instead of the rotating globe, on which there is also a warning symbol (triangle with exclamation mark), then network access does not work. In addition to the failed Internet access due to an incorrect connection, this macOS recovery error message can also appear if the network configurations made are not compatible with the process. Solutions suggested by Apple are here:

  • When starting the Apple Mac, press the key combination Command + R (or cmd + R or ⌘ + R) to solve the system restore with local resources instead of via the Internet
  • Instead of a WLAN connection, set up a wired LAN connection using an Ethernet cable
  • Perhaps choose a different network for the Internet connection
  • Try again later if the problem is server-side

Prohibition symbol (crossed out circle)

First the good news: the icon doesn't mean the Apple Mac is broken. The circle with a solid line in the middle means that there is a macOS version on the startup disk, but it is not compatible with the Mac model. With the link above for keyboard shortcuts for the Mac start you will find ways to install a compatible macOS on your Mac - the original one from the time of manufacture (⇧ + ⌥ + ⌘ + R), the last compatible one (⌘ + ⌘ + R ) or the last installed one (⌘ + R).

Folder with question mark

If a folder with a question mark is displayed when the Mac starts, the startup volume (i.e. the local hard drive) is recognized, but not the macOS operating system on it. The symbol can also indicate that macOS is not yet installed on the selected memory. It can also help here to use one of the above key combinations when restarting the computer. If you want to create a boot or installation medium on another Mac, you can of course do that too - here is one Instructions for macOS Catalina.

Flashing question mark on Mac startup

If a flashing question symbol appears instead of the folder symbol with a question mark, it can have different meanings. If it only appears briefly and then the Mac starts normally, then only the startup disk needs to be reassigned. Because if the question mark is only displayed for a few seconds, it means that the Mac cannot find any macOS on the currently selected volume. Then he searches on another storage medium, finds it there and boots. If this does not happen and the question mark is displayed continuously or flashes, then a macOS recovery is necessary. You may need to use Disk Utility to repair the startup disk. All details can be found in the Apple support document HT204323.

Lock icon

If you want to start a Mac using macOS recovery, an external drive, a boot USB stick or the like, this can work without any problems. However, if a firmware password has been set up, this will first be requested to ensure that an authorized user tries to access it via an unusual start-up process. You can continue with the external storage medium, network start or similar after entering the firmware password. The lock only symbolizes that you have to enter the necessary "key" for verification in order to make important changes or to be able to use a new boot procedure.

PIN code entry is required

If the Mac displays an input mask for a (four or six-digit) PIN code when booting, this may (depending on the version) be combined with an Apple logo and the phrase "Enter the PIN code used to protect your system to unprotect this Mac.“Done. The display means that the device has been locked using the “Where is?” Function. Either you did it yourself accidentally (with an iPhone, iPad or other Mac on which the same Apple ID is used), the previous owner did it, or you should return the stolen Mac;) (Explanation : HT204756)

A USB, Thunderbolt, or FireWire icon appears when the Mac boots

If a large Thunderbolt, USB or FireWire symbol is displayed instead of one of the symbols described above when the Apple Mac boots, this means that hard disk mode is activated. This means that the Mac is connected to another Mac via the connection shown and is used by it as a storage medium (hard disk). You can find details on hard drive mode in the Apple support document HT201462.

Symbols and error messages when booting the Apple Mac

If you see unusual symbols when starting the Apple Mac, this does not necessarily mean an error or a defective hard drive. Some symbols or the absence of any graphics are even completely normal. The displays described appear depending on the mode, start attempt, restoration or backup. The source for this guide was the document as well as the Apple documents that were already linked HT204156. If you have further questions on the topic, please leave a comment :)

Mac guides, manuals, books, and more

Here in the blog you will find numerous help articles, instructions, guides and book recommendations for everything to do with the Apple Mac, the iMac and the various MacBook models. In addition, there are iPhone, iPad, Apple TV, Apple Watch and the various operating systems such as macOS, iOS, iPadOS, watchOS, etc. All of them can have a few hurdles, errors or the like around the system start. I hope that the guide here was able to help you solve problems on your Mac. Otherwise, please have a look through the articles in the following list:

You can find even more information and help - also and above all on Apple devices, operating systems and apps - at Sir Applerot Forum as well as once a week Sir Apfelot newsletter. Just take a look.

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  1. Alex Strippel says:

    "When updating macOS or reinstalling the operating system, the Apple logo and the loading bar may be displayed for a long time."

    Hello, I just restored my Time Machine BackUp to a stick. That took about 4 hours and when I got back to the computer I saw the apple logo and the fully loaded loading bar.
    You wrote above that it can stay longer. What does longer mean?

    • sir appleot says:

      If I'm not sure how long it will take, I usually give the Mac one night to finish. But only with old models. Newer Macs should have the complete installation ready in 1-2 hours. But it depends a lot on the Mac and whether you take over the old user data, because the migration assistant has been idle for a long time.

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