13 quick fixes to macOS Mojave problems

Dark mode, dynamic desktop, stacks, security enhancements, and more: macOS Mojave introduced many new features and improvements to macOS. But like any other operating system, Mojave isn’t without its glitches, bugs, and all kinds of compatibility paradoxes. In this article, we’ll cover common macOS Mojave problems and explain how to solve them.

Before September 2018, macOS Mojave was only available as a Beta via an Apple developer account. If you want to get early access to future OS updates, you might consider becoming an Apple Developer. This privileged club costs $99 per year to join, and in exchange, you’ll be the first to lay your hands on Apple’s fresh releases. 

List of most common Mojave problems

Here is the list of the most common Mojave issues that have been reported so far:

  1. macOS Mojave installation fails
  2. Can’t install Mojave on an external drive
  3. iCloud not syncing
  4. Bluetooth issues on macOS Mojave
  5. Mojave stuck on Login Screen or crashing
  6. Mojave slow or freezing
  7. Quit apps keep showing in the Dock
  8. Third-party apps not working on Mojave
  9. Time machine not working
  10. macOS Mojave battery problems
  11. Wi-Fi not working
  12. File thumbnails don’t show on desktop
  13. Zero-day bug
macOS Mojave won't install

1. macOS Mojave install stuck

can't install macos mojave

Is your Mac compatible with macOS Mojave?

One of the most reported macOS Mojave problems is a Mac getting stuck in the middle of the Mojave installation. A simple explanation — your Mac is just not technically fit to run Mojave. According to Apple, macOS 10.14 can be launched only on Macs not older than 2012. If yours was released earlier — sorry, you’ll have to miss this update.

Below is the list of Mac models compatible with Mojave:

  • MacBook (Early 2015 or higher)
  • MacBook Air (Mid 2012 or higher)
  • MacBook Pro (Mid 2012 or higher)
  • Mac Mini (Late 2012 or higher)
  • iMac (Late 2012 or higher)
  • iMac Pro (2017)
  • Mac Pro (Late 2013, mid-2010, mid-2012 models)

Try reinstalling macOS Mojave from scratch

Okay, let’s assume your Mac is fully compatible with macOS Mojave. But still, you get something like “Installation of macOS could not continue” on your screen. What’s causing the installation trouble, then? If your Mojave update stuck or ends abruptly, you should go back to square one and do it properly this time. The recommended procedure requires backing your Mac up and cleaning your Mac from “old baggage” that may interfere with the macOS update.

Step 1. Clean up your Mac from system junk

As a general rule, a fresh macOS requires a fresh hard drive. There are tons of outdated caches, app leftovers, plugins, and system logs on any given Mac. Not only do they take up a lot of space, but they may also be causing various kernel-level errors. To clear them away, use a dedicated Mac cleanup app — you’ll be able to delete hidden junk that you otherwise can’t access. Among many alternatives, the simpler solution is CleanMyMac X, which has proved quite effective in cleaning my MacBook Pro (15-inch, 512 GB).

CleanMyMac X - Smart Scan complete

  1. Download CleanMyMac for free from the developer’s site.
  2. Click Smart Scan.
  3. Remove hidden junk from all the suggested folders.

Now your Mac is ready to install macOS Mojave on top of your current OS. What’s left is to prepare the data backup in case something goes wrong.

Step 2. Back up your Mac

  1. Connect the external drive and open Time Machine.
  2. Switch Time Machine to the “On” position.
  3. Choose the external drive as a backup path.
  4. Click “Backup Now.”

Step 3. Reinstall macOS Mojave

Now, delete the previously downloaded macOS Mojave installation (find it in your Downloads) and restart your computer. Next up, re-download the installation file from your Apple Developer Account or the Mac App Store.

What else you might try

You have downloaded the macOS Mojave and still cannot go past the “Preparing the installation…” window. Let’s admit, new macOS versions are often buggy and problematic, but here are a few more ideas to try:

  • Start your Mac in recovery mode. To enter recovery mode on Mojave, Click Apple logo > Restart. Right after that, hold down the Command + R buttons while your Mac is restarting. While in recovery mode, you’ll be able to run Disk Utility to check your disk for consistency.

  • Disable your antivirus software if you have any installed. Sometimes, such apps would block any new installation attempts — a classic case of overprotection.

problems installing macOS Mojave beta

2. Can’t install the Mojave on an external drive

Some folks have reported they have run into trouble trying to install macOS Mojave onto an external SSD drive. The installation would abort midway and eventually drop you back into High Sierra. As some bloggers have pointed out, the issue is caused by a USB-C adapter connected to MacBook.

The solution suggested on Mac forums would be to connect the SSD via Thunderbolt 3 port. If you haven’t got a similar dock available, but your external drive has a Thunderbolt 1 or 2 port, try connecting it directly using a Thunderbolt 3 to 2 adaptor. Hopefully, this time it should work.

One more suggestion is to go the radical way and perform a clean install of macOS 10.13 High Sierra and then go one step up to macOS Mojave.

3. iCloud is not syncing properly

The first editions of macOS 10.14 Mojave seemed to be lacking some basic iCloud features, which will likely be added in the next updates. One of those missing bits is Back to My Mac functionality (remote access to files and screen sharing). But the most annoying setback is iCloud not syncing properly.

iCloud issues macOS Mojave

How to fix it? First, sign out from the iCloud account and sign in back again.

  1. Select Apple icon > System Preferences.
  2. Select iCloud > Sign Out.

Then, similarly, log in back to your account. If that doesn’t resolve the syncing issue, delete the iCloud-linked folder “Cloud Docs” in the Finder. This will cause your Mac to download iCloud drive files and re-establish the connection.

  1. Click on Finder > Go > Go to folder… (in the upper menu).
  2. Find the CloudDocs folder and delete it.

In addition to that, you’d want to stop a couple of iCloud-related processes in Activity Monitor. This will reboot iCloud syncing from the ground up.

Activity Monitor Mojave Freezing
  1. Go to LaunchPad > Activity Monitor.
  2. Type “cloud” in the search bar above.
  3. Click on the big [x] Quit button.

Repeat the same steps for the “bird” process.

Since iMessage syncing has been added to macOS Mojave (cool!), this may not work properly after the update. To fix it, you must apply the ancient “switch it off and on again” principle that works equally well for your home appliances. Simply disable and then re-enable iMessage syncing via iCloud to get it going as it should.


4. Bluetooth issues on macOS Mojave

Bluetooth connection not working on macOS 10.14 Mojave is a known issue, too. The symptoms look like your Mac just wouldn’t connect to Bluetooth or, in some cases, refused to turn itself off.

To address this injustice, it’s recommended to delete the Bluetooth plist file — don’t worry, it will recreate itself upon the next Bluetooth launch. But just in case, copy the file to some safe location.

  1. Click on Finder > Go to Folder…
  2. Type in /Library/Preferences.
  3. Find com.apple.Bluetooth.plist file and delete it.
  4. Restart your Mac.

5. macOS Mojave crashing at login

This macOS Mojave problem is quite typical. Unfortunately, not all the apps are updated to meet every macOS requirement, so it often happens that an app crashes on your Mac startup and makes the whole OS slow and unresponsive. This is what you can do about this:

Disable the unwanted Login Items

So how can you fix macOS Mojave crashing at login? Luckily, this issue is nicely tackled with the previously mentioned CleanMyMac X. It allows you to remove Login Items one by one so you can see which app was causing the macOS to crash. Disabling Login items with CleanMyMac at first may seem as an extra step, but it’s worth it.

  1. Download CleanMyMac X — a free download from the developer’s site.
  2. In the sidebar, find Optimization > Login items.
  3. Disable potentially problematic Login Items.
CleanMyMac X - Login items

Using the same tool, you can also trim down the so-called Launch Agents or Daemons. These are small helper applications that run in the background and extend the main app’s functionality, like Skype. Once again, your logic is to switch off one app at a time to see if it fixes the problem.

Delete specific plist files in Preferences

A user on the MacRumors forum suggested another possible solution. This annoying macOS Mojave problem can be fixed by removing the potentially corrupted property list (plist) files in Preferences. These files contain individual user settings for various parts of the macOS (Finder, Desktop, Applications). Resetting them may be just the solution you need. To proceed, you will need to start your Mac in safe mode.

To enter safe mode, hold down Shift when your Mac is booting up. Let go of the Shift key when you see the Apple logo appearing on the screen.

Preferences macOS Mojave 2018

1. Click Finder > Go > Go to Folder…
2. Paste in: ~/Library/Preferences/
Note: copy this entire folder
3. Delete plist files for Finder or Desktop.

Restart your computer to see if that fixed the issue. If not, the optimal solution would be to revert to macOS High Sierra and wait for the next macOS Mojave updates from Apple. To go back to your previous macOS, install it from the Time Machine backup that we are sure you had meticulously prepared.

macOS Mojave crashing slow Mac

6. Mac running slow after Mojave update

So you’ve successfully installed macOS 10.14 Mojave to find out that your Mac’s performance got worse. This may not be a Mojave-specific issue, though. Normally, people judge the efficiency of their Mac by looking at the speed of their most-used apps. If your Mac hangs while you’re using Skype, for example, this may be due to Skype conflicting with the Mojave, thus a completely app-related problem. But, anyway, it’s a good idea to do a basic health check of your system. 

Fixes for slow performance on Mojave:

1. Clean up your Desktop

Desktop issues stack macOS Mojave

Remember, every desktop icon takes up RAM space. The fewer icons you have, the faster your Mac gets. When your Desktop is clean, restart your computer. The newly introduced “Desktop Stacks” feature on macOS Mojave lets you put those icons in order.

2. Update all your apps to their latest versions

What may seem like a problem with macOS Mojave can be an issue caused by your outdated software. Except for bug fixes, updates contain essential improvements to ensure the app can run smoothly on all versions of the OS. Keep your programs up-to-made to avoid vulnerabilities and slow performance.

3. Check your Activity Monitor

Go to Launchpad > Activity monitor. Quit apps and processes that take up an unfair amount of memory.

4. Remove system junk and app cache

Outdated cache files, redundant support files, and logs generated by all your apps can slow even a powerful Mac down to a crawl. Remember how fast and efficient your Mac was straight from the store? You can partially restore this original power by cleaning up your Mac from top to bottom or from Finder to Library if you like. CleanMyMac X is a great app that can clean all sorts of junk and clutter from your hard drive.

Things that deserve being removed:

  • System junk
  • App caches 
  • Unused apps 
  • Old iOS updates
  • Extra localizations

You can download a free CleanMyMac version here. It cleans all the items described above.

7. Quit apps keep showing in the Dock

The latest update to macOS Mojave introduced a new feature that leaves many of us, Apple fans, disappointed. Now the default behavior of macOS Mojave is to show you the 3 most recently used applications in the Dock. So if you have just quit an app and it still shows up in the Dock, it’s not a bug but a feature. Luckily, an easily reversible one.

  1. Go to System Preferences > Dock.
  2. Deselect “Show recent applications in Dock.”

After all, the Dock is a customizable corner of the macOS, and it should be left to the user to decide what to put in there.

8. Third-party apps not working on macOS Mojave

Apps not working on macOS Mojave

The main problem here is the 32-bit/62-bit distinction. Apple stated that macOS High Sierra is the last operating system to support 32-bit optimized applications. From then on, if an app isn’t updated for 64-bit architecture, you won’t be able to use it on Mojave. This is one of the reasons not to update and stay with the good old High Sierra on your Mac.

How to find apps that are not Mojave-compatible?

Before you upgrade to macOS Mojave, check for compatibility issues. Here’s how to do that:

  1. Click on Apple logo > About this Mac.
  2. Click on System report > Applications. 

Now, look for the last column 64- bit in the window that opens. “Yes” indicates that the app in question is ready to run on macOS Mojave. Sadly enough, even some of Apple’s native 32-bit apps will not be supported on macOS Mojave. This includes Aperture, an old version of iWork, and the old version of Final Cut Studio. 

Other notable 32-bit apps are Microsoft Office’s Powerpoint 2011, Outlook 2011, Word 2011, and Excel 2011. The adequate answer to that is to update these apps to newer versions. Or you could also:

  • Run macOS Mojave alongside macOS High Sierra with Parallels.
  • Choose not to update to macOS Mojave.
  • Reach out to the app’s developer and ask them for advice.
  • Consider transitioning to a different app.

How to check 32-bit apps on macOS Mojave

However, if you’ve already upgraded to macOS Mojave and need to check the incompatible software, you have to follow different steps than mentioned above. In Mojave, 32-bit apps can be reviewed in System Information:

  1. Click on Apple logo > About This Mac.
  2. Click on System Report.
  3. Choose Software > Legacy Software.

That’s how you can get an overview of 32-bit apps on your Mac if Mojave is installed on your Mac. Developers are highly encouraged to migrate to a 64-bit framework, but it will take some time. So, if you need to remove incompatible apps from your system, check a few tips below.

An app is “not optimized for your Mac and needs to be updated”

When you see this rather discouraging message, you may simply want to uninstall the app — a radical solution to the problem. To make things easier, the Uninstaller tool in CleanMyMac has a special tab that will show you all 32-bit apps you have on your Mac. From there, you are one click away from deleting them all at once:

My app is 64-bit but still not working on Mojave

This happens too. In this case, you can download the app again and try to reinstall it from scratch. There is a more elegant solution, though. CleanMyMac tool, mentioned in this article, has a tool to reset the apps to their original state, notably, without losing your user settings.

  1. Open CleanMyMac (Download it free here).
  2. Go to the Uninstaller section. 
  3. Select the application that you wish to reset.
  4. Click Reset in the dropdown menu.

Using this method, I successfully fixed my Evernote app, failing to sync after the last update. 

Since we’re talking app versions, one more use of this versatile program is to update your applications to the latest versions. Instead of googling for the latest version of apps X, Y, or Z, you can update everything in one shot — just what the Updater tool in CleanMyMac X does. 


9. Time machine is not working on Mojave

Many people report that after upgrading to macOS Mojave, Time Machine cannot complete a backup. Unfortunately, this problem isn’t fixed yet, so keep an eye on software updates in the Mac App Store. 


Before that, if you don’t want to risk losing your important files, consider some alternative backup options. You can transfer files to an external drive, iCloud, etc. For more information, check out this article about different ways to back up your Mac.


10. macOS Mojave battery problems

Since installing macOS Mojave, the battery life of your MacBook has become shorter? Then it’s time to check what’s causing the battery drain on your Mac. Here’s how to do that:

  1. Open Finder.
  2. Go to Applications > Utilities.
  3. Choose Activity Monitor.
  4. Click Energy.

From there, you can see how much energy your programs are taking up. If it’s a lot, you may consider uninstalling some apps.

If you want to monitor your battery health and get alerts when something goes wrong, I recommend using CleanMyMac’s Menu. One click, and you know the most resource-consuming apps, health indicators of your battery, hard drive, and memory.

You can also check an article about increasing Mac battery life; it’s full of useful tips.


11. Wi-Fi not working after installing Mojave

If you’re having trouble connecting to the internet, try starting your Mac in safe mode and check the connection. If you’re not sure how to do that, here’s a detailed guide on how to use safe mode.

If Wi-Fi works in safe mode on Mojave, then it means there’s an issue with an app or extension you installed. Make sure that all your apps are updated to the latest versions to avoid compatibility issues. To do that quickly, use the Updater tool in CleanMyMac X utility. With its help, you can easily get the latest and the most reliable versions of your applications.

Here’s how to use CleanMyMac’s Updater:

  1. Download the app (for free) and open it.
  2. Choose the Updater tab.
  3. Select the app and click Update.

That’s it! Now you are up-to-date.  


12. File thumbnails don’t show on the desktop

Some people reported that after installing Mojave, thumbnail previews of some files, such as photos and PDFs, don’t show up.

One thing you can try is removing the cache files by starting your Mac in safe mode, then shutting it down and restarting normally. But I recommend using CleanMyMac in this case. It helped me get all my file previews back. After opening the app, go to System Junk to remove the caches and then use the Maintenance utility to Run Maintenance Scripts.

Maintenance Scripts in CleanMyMac X


13. Zero-day bug

A zero-day vulnerability was revealed by security researcher Patrick Wardle just after the Mojave launch. This bug can allow an attacker to use a malicious app in order to steal your personal data, such as contact details from your Mac.

Patrick highlighted it on Twitter with a video that shows how he tries to access the address book on Mojave and fails before running a script simulating a malicious app that finally allows accessing the address book and copying the data.


Apple later addressed and fixed this bug. Although the user data is safer in Mojave, there’re still situations where you can’t be fully protected. That’s why it’s important to update your software and OS as soon as updates are released.

With several drawbacks mentioned in this article, macOS 10.14 Mojave still looks and feels great. A new macOS Mojave 10.14.6 supplemental update fixed several issues and included the relaunch of Safari 14, which is promised to be running correctly now. So, if you’ve already updated your Mac to Mojave, welcome to the Dark Side Mode!

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