How to Fix the Most Common macOS Catalina Issues

Troubleshooting probems with Apple's latest operating system

You may encounter some macOS Catalina issues either before or after you upgrade to this version of Apple's operating system. Some possible issues include:

  • Inability to download macOS Catalina.
  • Trouble installing the new operating system.
  • Inability to log in to your computer after installing Catalina.
  • Problems running apps.
  • Trouble with using a keyboard or mouse.

These issues have a variety of causes and solutions.

How to Fix Common macOS Catalina Issues

How to Fix macOS Catalina Issues During Download and Installation

If you're trying to upgrade to macOS Catalina and can't even get the installer to download––or it won't run even if you can get it––here are some things to try.

  1. Check to see if your Mac is compatible. If you get an error when you're trying to download the macOS Catalina installer from the Mac App Store, one possible explanation is that your computer is either too old or lacks the hardware necessary to run the operating system. Here are the Mac versions compatible for the upgrade:

    Your Mac also needs to be running Mac OS X Mavericks (10.9) or later.

    • MacBook Air/Pro: Mid-2012 and newer
    • Mac Mini: Late 2012 and newer
    • iMac: Late 2012 and newer
    • Mac Pro: Late 2013 and newer
    • MacBook: Early 2015 and newer
    • iMac Pro: 2017

    If you don't have one of these Macs, you won't be able to make the update.

  2. Try the download another time. It's not common this far out from the initial release, but it's possible that your download of the macOS Catalina installer is failing because Apple's servers are crowded. This problem is more likely to happen on the day of a new release or update, but if you try your download again at a less busy time (like the middle of the night), you might have more success.

  3. Make sure you have enough hard drive space. Depending on which version of Mac OS X or macOS you're currently running, you have different room requirements for the installer. Here's what you need:

    • 12.5 GB of disk space–if running OS X El Capitan (10.11) and up
    • Up to 18.5 GB of disk space–if running OS X Mavericks (10.9) or Yosemite (10.10)

    If you don't have enough space for the installer file, you should delete or transfer files to make room.

  4. Find the macOS Catalina Installer app. Usually, the installation will begin automatically when you download the file. If it doesn't, you can manually start it by opening the app your Mac downloaded. The logical place to look for the installer is in your Downloads folder, but it isn't there. It'll actually end up in your Applications.

  5. Restart your computer for other problems. If your computer hangs during the initial setup, you may need to force it to restart. Hold the Power button for a few seconds until the Mac shuts down, and then press it again to restart.

  6. Use Disk Utility. For additional macOS Catalina issues during startup that restarting won't fix, you may need to use Disk Utility to make sure your hard drive is okay. Start your Mac in Recovery Mode by holding Command+R while it starts up. From this safe mode, you can run diagnostics, repair your hard drive, and even reinstall macOS if necessary.

How to Fix MacOS Catalina Login Issues

Once you've installed macOS Catalina, you may have some issues logging in. Here are some steps to try if you either can't log in or your computer logs you out of your account while you're using it.

  1. Restart your Mac. Giving your computer a fresh start is the solution to a lot of problems; that's why it reboots immediately after you install a new version of the OS.

  2. Create a new admin account. One possibility is that the installation corrupted your primary administrator account. Creating a new one as a workaround might solve the problem.

  3. Reset your admin account using a Terminal prompt. To keep your admin account intact but still fix the problem, you need to remove the file that's causing the issue. Follow these steps to do so:

    1. Restart your computer while holding Command+S.
    2. Type the following command into the terminal window: /sbin/mount -uw /.
    3. Press Enter.
    4. Type rm /var/db/.applesetupdone.
    5. Press Enter.
    6. Log in to your account.
  4. It should be working properly now.

How to Fix macOS Catalina Issues with Peripherals

In some cases, you may have trouble using your mouse, keyboard, or features like Bluetooth after you update macOS. Just like with a problematic administrator account, you can fix many of these issues by removing files. Here's what to do.

We're going to talk about files called 'plist.' These kinds of files are only called plist on Macs. They are short for Property List and in these examples the files contain information like which side of the screen you want to have the Mac's dock. If, for some reason, the file won't accept changes you can delete the plist and the app (in this case the Mac's dock) will just create a new one with default settings from Apple.

  1. If your MacBook keyboard doesn't work, restart your Mac. When you reach the Finder, close your MacBook. Wait a few seconds, and then open it again.

  2. If your mouse doesn't work, follow these steps:

    1. Open the Finder's Go menu while holding Option, and then click Library.
    2. Navigate to the Preferences folder inside Library.
    3. Delete the files called and 
    4. Restart your computer.
  3. If you can't use Bluetooth, follow these steps:

    1. Open the Finder's Go menu while holding Option, and then click Library.
    2. Navigate to the Preferences folder inside Library.
    3. Delete the file called
    4. Restart your computer.
  4. If the Finder crashes, follow these steps.

  1. Open the Finder's Go menu while holding Option, and then click Library.
  2. Navigate to the Preferences folder inside Library.
  3. Delete the file called
  4. Restart your computer.

How to Fix macOS Catalina Issues with Applications

Once you get Catalina up and running, you may have some problems with the applications you've installed. Some may not work the same way anymore, and others may not run as well as they did before. Here are some solutions you can try to get things working again.

  1. Check for updates. As Apple changes macOS, app developers sometimes need to make their own updates to keep them working. Open the App Store to see if a new version of the problem app is available.

  2. Check for compatibility. Unfortunately, once you upgrade to Catalina, some older apps won't work anymore. The problem is that Catalina no longer supports 32-bit apps in favor of 64-bit ones.

    No fix is available for this problem, unless the developers upgrade their apps to work in Catalina. If you lose the ability to use an app that you depend on, your best solution may be to downgrade to an earlier version of macOS.

  3. With other app-specific issues, especially for stock apps like Mail, you may see some normal functions either not working or nonexistent. Follow these steps to get them working again.

    1. Close the app completely.
    2. Reopen it while holding Shift to enter its safe mode.
    3. Close down the app again.
    4. Open it while holding Shift to turn off safe mode.
    5. Restart your computer.
  4. For issues with Mail, you may have some files that didn't transfer properly. Follow these steps to try to remove them.

  1. Open the Finder's Go menu while holding Option, and then click Library.
  2. Follow this file path: ~/Library/Containers/ Application State/
  3. Find a file called and drag it to the Trash.
  4. In the Containers folder, find and Drag those to the Trash or to another folder of your choosing.
  5. In the Library folder, open the Mail folder and then the MailData folder.
  6. Delete Envelope Index, Envelope Index-shm, and Envelope Index-wal.
  7. Restart your computer.