Apple diagnostics not starting yosemite software#
Apple diagnostics not starting yosemite mac#

To Reset NVRAM, the same old key combination that has been used for generations of Macs (Command + Option + P + R) is used immediately upon reboot. When resetting NVRAM, this data is all wiped from the Mac, so you may need to readjust things like your screen resolution, mouse or trackpad tracking speeds, etc…

Apple diagnostics not starting yosemite mac#

So what does resetting NVRAM do for you? NVRAM stores information in-between boots of your Mac – things like the startup disk, video and display information, volume for the system startup chime and speaker, time zone information, default system fonts, and more. Those who have been around the Mac world for a long time remember the common term “zapping PRAM” (parameter RAM) – this is essentially the same process with a different name. Resetting the non-volatile random access memory (NVRAM) on your Mac can sometimes vanquish the white screen. After removing a login item from the list and verifying that the system boots normally afterward, you may wish to contact the developer with a bug report or try removing and reinstalling that app.Īpple’s knowledge base has an excellent backgrounder on Safe Mode that’s worth reading. To remove an item, just highlight it by clicking on the item name, then click the minus sign ( – ) button below the list. Removing an item from login items is done by launching System Preferences, then selecting Users & Groups, and clicking on Login Items. If you know what apps were recently updated, try removing them from the list of login items and then reboot normally to see if the problem is fixed. This usually happens after a specific app that’s loading at bootup receives a buggy update. If rebooting the machine normally (without Safe Mode) still results in a white screen, it may be a login item causing the Mac to balk at loading. System Information shows that this Mac has booted into Safe Mode If it shows “Safe,” then the Mac is definitely in Safe Mode if it shows “Normal,” then the shift key may not have been pressed soon enough.

Apple diagnostics not starting yosemite software#

How can you make sure that your Mac booted into Safe Mode? The login screen displays the words “Safe Boot” in red in the upper-right corner, or you can launch Utilities > System Information, then click on Software and see what’s listed after “Boot Mode” in the System Software Overview (see image below). If you can boot a Mac successfully in Safe Mode, you either try to boot the Mac again to see if the next try is successful – perhaps just clearing some caches was what the doctor ordered. Essentially, Safe Mode disables some macOS features, clears some caches, and prevents some third-party kernel extensions from loading, all of which reduce the amount of work the Mac has to perform to get to the login screen. Safe Mode is a way to troubleshoot some system problems that can keep your Mac from booting normally. This progress bar indicates that Safe Mode is running a directory and disk check on your Mac this is like running First Aid from the Disk Utility. Keep holding down the shift key until the boot progress indicator shows up.

This is very easy to do: simply hold down the shift key on your keyboard as soon as you hear the Mac startup chime.

One time-honored trick to recover from a white screen is to boot into Safe Mode. However, if you find yourself a victim, please let us know in the comments section below!

Update: Ma– Because the White Screen of Death is a hardware/firmware issue, we are reasonably confident that it will not occur on M1 Macs under adverse startup conditions. In this article, we’ll describe some steps that you can take to recover from the dreaded white screen. There is no Apple logo on this display, nor will you see a progress bar showing where you are in the Mac boot process. You’ll know when you’ve been hit by this bug when you boot up your Mac and see a blank white display.

Usually, this rare bug happens after updating macOS to a new version, but it can happen at any time. This poor MacBook Air is experiencing the “white screen of death”įrom time to time, you may experience one of the more frustrating Mac glitches – a white screen during boot.