Common Problems During and After macOS High Sierra Installation

MacOS High Sierra is finally ready for release. It endured the summer beta program, and is now available through the Mac App Store for anyone to download and install.

(macOS High Sierra’s initial install screen.)

We’re always grateful that new versions of the operating system go through an extensive beta process, but it always seems a few issues will still be lurking, ready to pop up and surprise us.

With that in mind, here are some of the more common problems you may encounter when upgrading to macOS High Sierra.

Note: Before upgrading to any new or updated operating system, it’s a good idea to have a current backup in place.

Upgrading From the Beta
If you’re a beta tester, you may have a slightly more difficult time upgrading than the rest of us; it all depends on whether you installed the new APFS (Apple File System) during the beta testing. Apple backed away from its original goal of having APFS ready to go for all Mac configurations. Instead, it’s releasing macOS High Sierra with APFS only for Macs using SSDs (Solid State Drives). If you converted a Fusion drive during the beta, it needs to be reverted to HFS+ before you can install macOS High Sierra.

Unfortunately, Apple isn’t providing any tools to revert the file system. Instead, you’re required to back up your current data with Time Machine, erase and reformat the affected drive(s), install macOS High Sierra, and then migrate your backed up data to the fresh install.

Apple includes instructions for the process, specifically using Time Machine as the backup app. It seems you should also be able to perform this task by creating a clone using Carbon Copy Cloner or one of the other popular cloning tools. Nevertheless, even if you decide to create a clone, we highly recommend you also create a Time Machine backup, especially if the clone is the only copy of your data you will have.

You’ll need a drive partitioned as HFS+ for the Time Machine backup. This can be an existing Time Machine drive as long as it’s formatted as HFS+. You’ll also need to create a bootable macOS High Sierra installer; a 16 GB or larger USB flash drive or an external drive can serve this purpose.

Warning: The process of creating the bootable installer will erase the contents of the selected drive volume.

Apple has posted instructions in its support area for Preparing Your Fusion Drive Mac for the macOS High Sierra Install. It covers two methods for converting a Fusion Drive back to HFS+ and installing macOS High Sierra. The instructions are a bit sparse, but should be sufficient for getting the job done. If you have any questions regarding the process, be sure to post them in the Comments section below.

Downloading macOS High Sierra From the Mac App Store Stalls
The process of downloading High Sierra from the Mac App Store should be an easy one, but a few of us have run into a problem where the download seems to fail to start, or freezes if it does begin.

(If your download of macOS High Sierra seems to stall you may need to restart the Mac App Store.)

In both cases, patience may be the best course of action. But if after a reasonable amount of time, say 15 minutes to half an hour, there’s been no change, then it’s time for action.

Open your web browser to any page; the idea is just to verify that your Internet connection is working. If you’re having network issues, they need to be addressed before continuing.

Quit the Mac App Store. If it fails to respond to the quit command, force quit by selecting Force Quit from the Apple menu. In the Force Quit Applications window that opens, select App Store, and then click the Force Quit button. You’ll be asked if you really want to force quit the App Store; click the Force Quit button.

Once the Mac App Store finally quits, go ahead and restart the store. Select macOS High Sierra and start the download again. If you still have problems, quit the Mac App Store (using force quit, if needed), and then restart your Mac.

Return to the Mac App Store and try again.

Freeze During Installation
After you start the macOS High Sierra installation process, you may notice that your Mac’s screen has gone black, and nothing seems to be happening. The likely culprit is that your Mac has frozen during the restart process. The installation process copies needed files to the destination drive, including a minimum boot environment. Once everything is in place, your Mac should restart and finish the install process. If you’re stuck at the black screen, you should wait for a reasonable amount of time; no more than half an hour. If your Mac doesn’t finish the restart by then, go ahead and manually shut your Mac down by pressing and holding the power button.

(The installation of macOS High Sierra can stall on a totally black screen, or one with the status bar showing. Either way, be patient before forcing a restart.)

Once your Mac has shut down, you can restart it. Chances are your Mac will restart and pick up by displaying the Setup Assistant, ready to finish the install process.

If you still find yourself stuck, try shutting down again, but this time restart your Mac in Safe Mode. Once the desktop shows up, disable any startup items you may have set up, as well as any anti-virus apps you may have, and then restart your Mac. You’ll need to restart the macOS High Sierra installation process again.

If you’re still unable to resolve the problem, try booting up in Recovery Mode and using the Disk Utility option to check and repair your startup drive. Once your drive has a clean bill of health, use the Reinstall macOS option to ensure the startup drive’s operating system is intact. Once you return to the desktop, you can restart the install process.

Slow Performance After Install
Some temporary performance issues can be attributed to spotlight indexing that may be running; after all, there’s a lot of new data on the drive that needs to be catalogued. Time Machine can also become active soon after an install and slow things down a bit.

Waiting a short time will likely see the slowness clear itself up with no intervention on your part. Should the slowness continue, you can try the tips outlined in Tech 101: How to Clear Cache and Temp Files.

Wi-Fi Issues
When macOS Sierra was released we saw quite a few Wi-Fi-related issues, which we address in the guide: Common Problems After Installing macOS Sierra.

Thankfully, at least so far, we’re not seeing a repeat of major Wi-Fi issues. But that’s not to say there aren’t at least a few of them. During the beta, there was a recurring problem with connecting to a personal hotspot, such as one provided by an iPhone. The solution was simple enough: just turn Wi-Fi off and back on again, the ultimate IT solution for most problems.

(Turning Wi-Fi off and then on again can restore a connection that doesn’t work after installing High Sierra.)

To turn Wi-Fi off, select Turn Wi-Fi Off from the Wi-Fi status icon in the menu bar.

To turn Wi-Fi back on, select Turn Wi-Fi On from the Wi-Fi status icon.

If you don’t see the Wi-Fi status icon in your menu bar, launch System Preferences from your Dock or Apple menu, and select the Network preference pane.

Place a check mark in the Show Wi-Fi Status in Menu Bar box.

Apps Not Working
Unfortunately, it’s the nature of progress that some apps get left behind when operating systems are updated. If you have an app that has stopped working under macOS High Sierra, you should check with the developer to see if any updates have been released, or will be released.

You can also check with RoaringApps, a site that gathers information about which apps work with what version of the Mac operating system.

(Sometimes an app may fail to complete launching, or behave strangely when a new version of the macOS is released.)

If you believe the app that you’re having problems with should work with macOS High Sierra, you can try deleting the app’s cache files. Here’s how to do that:

Quit the app in question, if it’s currently running.

Open a Finder window or click on the desktop to ensure the Finder is the front most application.

From the Finder’s Go menu, select Go to Folder.

In the sheet that opens, enter the following: ~/Library/Caches

From the Finder window that opens, find the folder whose title includes the name of the app you’re having issues with.

Open the app’s cache folder, and delete any items within it.

Reset the PRAM/NVRAM, and then launch the app in question.

With any luck, the app should now be able to launch and work correctly.

Additional Rocket Yard Reading



  • Mail won’t open now I have installed High Sierra any ideas? Thank you

  • I had serious problems installing HS on one of my MBP:s. Install freezed when the startup bar reached the right most end. I made several tries. Used every hint you write about but to no avail. After some extensive detective work I found out that if I unloaded the kext that was connected to a HP printer, the install process worked like a dream.

  • files won’t copy to/from usb drive to fusion drive.

  • Files won’t copy from USB drove to fusion drove.

  • After downloading the High Sierra from the app store do I still need internet connection for the installation on my Mac? Thanks

  • Need to correct my previous comment. That fix did work but only for a couple of hours. I think High Sierra have some glitches and am hoping Apple will soon provide an update. This is very annoying when Face Timing with the Grand Kids.

  • Came across this on Apple site and it appears to solve my problem.
    Here is the link to Apple.

  • Up graded to High Sierra and now my FaceTime camera freezes as well as Photo Booth. I am assuming an update will be out soon.

  • I’m having trouble with ICC profiles not printing as good as in Sierra AND emails sent to me as a reply, come in 100% black w/no ability to see and image…only read text.

  • Logitech Web Cam Software work well with Sierra. But in High Sierra, it keep on saying some applications use it already.

  • SD Cards (Fat32) not appearing on the desktop of high sierra – disk utility says mounted, not appearing – tried first aid, no luck, thoughts anyone?

  • could not load security & privacy preference pane. mac OS high sierra

  • the High Sierra update completely destroyed my OWC 1TB SSD drive. I can’t even get my machine to recognize the drive now. after hours of trying to get it to work (or even recognize the drive in Recovery Mode), I’m having to take the entire computer in to see if someone else can repair the drive. it’s been a nightmare.

    • For some odd reason, it rolled back my boot drive to March, which is especially odd insofar as I don’t have any Time Machine backups from that long ago.

    • I had the exact same problem on my macbook pro with the same SSD drive. After upgrade attempt, the SSD drive would not mount and be recognized. Ended up erasing the SSD drive and restoring everything from time machine. I’m not going to try HS upgrade for a long time now.

    • This is the kind of situation for which you need an emergency utility disk or, better yet, a recent (before the upgrade to 10.13) clone of your system. If you don’t back up before a major upgrade you’re just asking for trouble. Which appears to be the problem in your case. If you had an external boot drive you could use Disk Utility to see if your SSD really was hosed. At a minimum you would still have a viable system to work with.

      It never ceases to amaze me that so many people don’t take backing up seriously. Every time there is a macOS upgrade, and sometimes with updates too, there are people complaining about how the upgrade/update messed up their systems. I’m tempted to say they deserve what they get, but that would be cruel, wouldn’t it?

      Instead, we should be grateful for early adopters. By troubleshooting the new system for us, they save everyone else all sorts of trouble. In the meantime we can sit back and enjoy our sangfroid.

      That said, Otherworld has reported that some of their SSDs are incompatible with High Sierra and that they are working with Apple to resolve the issue. But that warning obviously came to late for you. They claim they e-mailed warnings to buyers of the affected SSDs, but apparently that message didn’t reach everyone. If your SSD is not on the list, perhaps it should be. You should contact Otherworld directly about this.

    • Try installing snow leopard (or any old install disk) and make a new install. I had same problem and this unlocked the volume on the hd needed to partition the hd.

  • I did a clean install on my Late 2011 27 inch I7 sandy bridge iMac and then performed a Migration from a Bootable external Clone. Everything is working perfectly and fast. My only problem is I no longer have a recovery disk. Did Apple remove this feature in High Sierra? Its a nice feature—- Glad I always keep a clone

    • First, how did you check to see if you have a Recovery partition with High Sierra? The easiest way to check is to boot into the Startup Manager by holding down the Option key at startup. Before you do this, disconnect any external drives so that you will see only your internal boot drive—and the Recovery HD if it exists. If you don’t see one here then, yes, for some reason your recovery partition was not created. I had this problem way back with Lion, but haven’t seen it since.

      Carbon Copy Cloner can create a Recovery HD partition when you clone a drive. This may be a problem, though, it you don’t have a High Sierra Recovery partition to copy. There are ways to add a recovery partition to a drive, but it’s tricky and, in any case, you need a copy of the relevant partition to copy from. You could try to create one by reinstalling High Sierra on another external drive, but that may be more trouble than it’s worth.

  • Crowd-sourced Application compatibility & feature support for macOS, iOS & Windows:

    RoaringApps – Application compatibility table

  • I was able to convert one of my Time Machine HDD to APFS, however TM will not use APFS. Disk utility would only display APFS options when trying to erase the APFS drive. I ended up telling TM to stop using that disk and then use that disk. TM then erased and used compatible format.

    We use our Mac mini for centralized backup. Had to delete centralized backups to get things working again. For the laptop on High Sierra it thought its backup was already in use. I stoped and restarted backup after deleting it on the server. For the non HS iMac, I told it to stop using the server, however it was unable to find the server again. Finder can find the server. So I guess it is back to usb drives for that machine. Maybe manually move the backup files to the server or different software?

  • The issue I have is this: High Sierra showed up in my App store and downloaded fine, however even though the App store says I updated on Oct. 1st when I click on about this Mac it still shows OS 10.12.6? I have both restarted and shut the computer down and re-opened and nothing….

    • It looks like you downloaded the High Sierra upgrade but did not run it. You would certainly know if you had. Look for the Install macOS High in your applications folder. If you find it, launch it and run the installer. If it’s not there you may be able to download it again.

  • I have a 2009 Mac Pro (4,1) that was upgraded to the (5,1) firmware before I installed 10.12. Running the betas of 10.13 was a smooth experience. However, when I started the install of the 10.13 released version, it said it needed to do a firmware update, and gave good instructions of what to do. Still, I was puzzled because this was never required for a Beta install. I wondered when did this firmware update get Beta tested? In the end, it took 4 tries to get the firmware update to run, and after that the installer ran fine and updated my third-party SSD boot drive to APFS without mentioning that it was doing this. I knew to expect this, but still…. Anyway, all is well now, but the firmware update problems left me worried that I would have a bricked machine.

    • I also had to update the firmware. Worked fine the first time, but killed my trackball driver in X12/X13.

      • I’ve had my Logitech wireless Trackball quit working after system updates so I keep my wired one handy. Usually, restarting solves the problem. So if you’ve got a wired mouse/trackball use it to select restart and you may be good to go or perhaps you may need to reconfigure it in the Preference pane. Also of course, check to see if new drivers may be available for your device. Just my 2¢.

    • Glad to hear the firmware update didn’t kill anything — I have the same setup and was leery. I’m betting it has to do with the new monitoring that is done weekly.

      • The instructions say to hold the power button until the light blinks or you get a long tone. I patiently held the button in each try, but only got the long tone on my last attempt. For me at least, no tone, no success.

  • Installed fine on our latest version of Mac Mini. Did not install APFS on fusion drive. I’ll wait till Apple supports that.

    My OWC Thunderbay required new driver after installing HS, even though I updated driver before installing HS. Speaking of which, SoftRAID says APFS will be fully supported in version 6.0. When will that come out and will it still be free upgrade?

    Apple moved file sharing and caching out of Server App and into MacOS. Not sure what to make of that.

    Photos does not automatically convert the library to the new high efficiency formats, in fact I haven’t seen any ability to convert the photos or library to high efficiency formats. I may have missed that. This maybe a good thing because the high efficiency formats use more CPU power and converting from lossy JPG to lossy high efficiency format may create more artifacts.

  • Drives with OWC SSD drives can not be upgraded to High Sierra at this time.
    When will this be fixed?

  • “firmware issues” trying to use an OWC SSD in a 2013 Mac Pro. What can we do?

    • Nothing (yet) apparently. I have this issue as well on my Late 2013 Mac Pro. It really would have been nice to have been notified about this proactively — not to mention it also would have been nice for an alert to be posted on this OWC site. Funny it’s not mentioned in the above article.

  • I installed High Sierra on a 2011 iMac and for some strange reason now I am an able to sign in to my iTunes account on that machine. Even the people at Apple can’t figure this out. Is anyone else having a similar problem?

  • I have just read more, including release notes from Apple’s Newsroom. The confusion around High Sierra and Fusion that I was having was brought about by the fact that the Beta version could be loaded onto a Fusion drive. However, in the release notes they are clear Fusion & HDD support for High Sierra will be coming, but not right now. Most of the loading information I read earlier was about actually removing High Sierra from an HDD based or Fusion based machine. I didn’t use the Beta so I don’t need to be concerned.

    I’m happy to wait. That’s good enough for me.

  • On my 09 mac tower, it installed fine. Some apps crash on launch, like System preferences(WTF). I’ll stay with Sierra for now.

  • I have a 4TB Aura SSD in a MAC Pro late 2013 that reports a firmware error on installing High Sierra. Tried reinstalling the original Apple drive, but the Mac won’t boot (black screen, high fan). Ideas?

    • Info with no solution:
      Tech at MacSales told me NOT to upgd High Sierra to the Aura. Instead, update the original Apple SSD because that would update firmware. Then, swap drives and update the Aura. When attempting to boot from the Apple drive, I had the same problem with blk scn and hi fan. Still had blk scn with fan disconnected. Tried to update the Apple drive when connected via USB but had a firmware warning after a restart. Fortunately, the Aura with Sierra was untouched and still works. Apple could have configured the update differently but it appears it is trying to make it difficult for after-mkt users. Typical. I hope someone will provide a utility that will update firmware but don’t have much hope.

    • I have exactly this problem as well.

      When I re-installed the Apple SSD, I got the black screen and high fan. I seem to remember doing an SMC reset in the past when I first installed the Aura and had this problem, but that didn’t work this time.

  • I have a Late 2009 iMac with an OWC SSD as it’s boot drive. Do you guys know if High Sierra will convert it to APFS right off the bat? Does it assume that this old Mac still has its spinning hard drive or does it recognize the aftermarket SSD and go forward with the automatic conversion? Thanks!

    • High Sierra updated to APFS on a third-party SSD in my 2010 MBP, so you should be fine.

      • no- aura ssds are NOT compatible with apfs file system- either you get a warning on installation that ‘installation failed due to a firmware…” or, worse, if you do get the installation to proceed with a few ‘recommended ‘ workarounds, some of which are suggested by owc, you end up with a corrupted or unusable ssd- owc now recommends ‘replacing the aura with the original ssd’ if you want to install High Sierra and apfs on a former aura pro system, then putting the aura back in, and clone the ORIGINAL ssd to the aura ssd, presumably from the external enclosure they sent (that doesn’t work- I did that and after ten tries, finally gave up)- owc needs to give us a firmware upgrade or our money back!

        • I have a late 2012 MBPro with Retina display and a 1TB
          OWC Aura 6G SSD. Everything seems to work properly except one of my backup disks will not mount properly: a WD Passport Ultra. My other WD backup (time machine) works and backs up properly

  • I’m a bit confused. All the pre-release information said that High Sierra will not be able to be loaded on HDD based or Fusion Drive based machines, yet Apple now has a guide for installing on Fusion Drive machines. When I read it, it looks like it is aimed at those who installed the Beta of High Sierra. Any ideas from anyone out there?

    • could not load security & privacy preference pane. mac OS high sierra, i need help plsss.

    • The release version of High Sierra will not run on a Fusion Drive in APFS format. The beta could do so; Apple’s instructions are about getting your Fusion Drive back to HFS+ so that you can run High Sierra on it—if you converted it while running the beta. A pain in the neck for beta testers.

      However, macOS 10.13 will run on a Fusion Drive in the old HFS+ format. It will also run on a regular hard drive in HFS+. And it can convert a HDD to APSF. If you want to convert a HDD, however, you will need to have a bootable drive or partition with High Sierra already installed. Only Disk Utility in High Sierra can do the conversion, and, of course, it cannot convert the drive it is running on. So this is a multi-step process that may, or may not, be worth the trouble.

      As APFS is so new there is really no real advantage to using it on a traditional hard drive. For one thing, the space saving features of High Sierra are unlikely to be of much use on a relatively large hard drive, including a Fusion Drive. It is intended primarily to help the small SSDs that come in Mac laptops these days. Given that Apple sells so many more laptop than desktop computers, this makes sense from their perspective. For a HDD or a Fusion Drive, APSF has little to offer and you will lose next to nothing by avoiding it.

      The biggest advantage to APSF on the Mac is for enhanced compatibility with iOS 11. iOS 10 converted the iPhones and iPads on which it was installed to APSF. The main advantage here is that it provides cloud sharing access to the files on your iOS device(s). The new image and video formats also save space on these devices, as most of them are even more limited in storage than Mac laptops.