• Upgrade macOS Mojave to macOS Catalina

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    I am still new with Macs so please bear with me.

    I have decided to upgrade to Catalina because I believe going to Big Sur is too big of a jump. I have never updated from one macOS to another so I am a bit anxious. I am just looking to see what people think of my steps to upgrade from Mojave to Catalina.

    1. Backup via Time Machine
    2. Download from https://support.apple.com/en-us/HT211683 (Do I need to use Safari or can I use Firefox?)
    3. Make sure all apps are closed
    4. Make sure there is power to my MacBook Air
    5. Start the update and hope for the best!

    Does anyone know about how long the upgrade process should take?

    Any tips would be gratefully appreciated.

    I am planning to do the update at the end of the month when I have some free time.

    Viewing 7 reply threads
    • #2376865

      Go to the System Preferences\Software Updates.


      Click on the Software Updates


      Be sure you choose Catalina, not Big Sur. May be under “Other updates.” Click on Upgrade now. It will download the installer, then require a reboot.
      Probably take an hour or so. Saves everything where it was.
      Be sure the MacBook doesn’t lose power for the duration.

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    • #2376870


      Hi PK,

      I get the same “screen” for Software Updates as you do with Big Sur being offered.  There is no “Other Updates”.  That’s why I think I need to download it from the link I posted above.

      Am I missing something?

    • #2376888

      You’ll need to visit this apple web page and use Safari to click on the link to download Catalina.  This will launch the app store which will download the actual installation app.  When the download completes, the installer will start automatically.

      The installer may take a fair bit of time to download, it’s somewhere between 8 and 9 GB.   Make sure you have enough disk space for that and roughly enough for Mojave plus Catalina temporarily during the upgrade.  It’s likely to take a long time, depending on the vintage and processor of your Air.



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    • #2376901

      I upgraded from Mojave to Catalina back when Catalina was the latest OS version. Took about an hour, no problems, piece of cake.

      I tried to update an iMAC from High Sierra to Mojave when Catalina was the latest version and I just couldn’t do it. That’s an analogous situation to what you’re doing as I understand it. (you’re skipping over one version of the mac OS, right?)

      At first I couldn’t download Mojave using Firefox. Then I figured out I needed to use Safari. That downloaded something but it just would not install. I gave up after a few hours and just installed Catalina. That took a couple hours on a 2017 base model iMac (i5 Intel, 8GB RAM and 1TB HDD – NOT an SSD).

      If I was in your position I, too would be tempted to try installing Catalina. I hope you have success!

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      • #2376919

        No I’m not skipping over one version of macOS.

        I am going from Mojave to Catalina.


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        • #2376923

          Correct. I did not say what I meant. There is a later version of the OS than the version to which you want to update, and that was also the case with my iMAC. That’s also, I believe, why you’re seeing Big Sur in Software Update but not Catalina, and why you’ll have to try and download and install Catalina. That is the analogous situation I faced and which I could not successfully accomplish. Not trying to be pessimistic, just letting you know what happened in a similar situation. Hopefully you’ll be able to do what you want.

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    • #2376903

      bassmanzam….my iMac came with Catalina.  When Big Sur came out, like you, I too was nervous about a major OS update on my first Mac experience. New things to learn, what would change, etc, etc.  I took the plunge and after a couple of weeks did the upgrade.  From my point of view, the changes were minimal for what I use my Mac for.  I think if do Catalina, in a short while you will wish you had gone straight to Big Sur.  I did the upgrade from System Preferences>Software Update  while using Chrome.  I’ve never heard the discussions above about using Safari to download the update.  That must apply to using the App Store I guess.


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      • #2376925

        I’ve upgraded the OS on a Mac a handful or so of times. I’ve had success every time I upgraded using Software Update. The one time I attempted an upgrade where the desired version did not show up on Software Update, I ran into trouble, and learned that, at that time at least, Safari was needed to download the desired OS. I did not find that on an Apple website but rather on something like 9to5Mac, where it was stated that many people had the same problem of not being able to download with any browser other than Safari.

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    • #2376904
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    • #2383346

      It took me long enough but I finally took the plunge and upgraded from Mojave to Catalina. Of course it’s been giving me anxiety for the past month but long story short the upgrade went smooth. Here are some of the highlights of the upgrade:

      * Used Safari to get old macOS updates from https://support.apple.com/en-us/HT211683
      * It basically linked to the App Store which I then clicked on to download the installer
      * Size of the file was 8.25 GB
      * Took only 15 minutes to download
      * After it downloaded it just froze for about 5 minutes
      * It finally started to do the install with the EULA and other stuff
      * Rebooted and “About time remaining” 26 minutes.
      * After 30 minutes it rebooted again. “About time remaining” 10 minutes
      * After 10 minutes the login screen came on.

      The only issue I don’t know how to handle is the “Relocated Items”. There was only one file:

      I am not sure what to do about this.

      Also, I have the following updates ready to install (Has anyone installed these updates?):
      * Catalina Security Update 2021-004
      * Safari 14.1.2

      All in all, I was presently surprised at how everything went.

      Thank you to all for your advice and encouragement to upgrade from Mojave to Catalina. Hopefully next summer I will upgrade to Big Sur unless I decide to do it earlier!



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      • #2383353

        I have installed all the updates on 5 machines (13″ MacBook Pro, iMac, and MacMini with i7 Ivy Bridge, 15″ MacBook Pro i7 Haswell and iMac4K i7 Kaby Lake), all with no problems.

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      • #2383356

        I’ve installed the Catalina 2021-004 and Safari 14.1.2 updates on a 2017 MacBook Air a week (or so) ago. No problems; about 5 minutes for Safari and 15 to 20 for Catalina. I’ll probably do the same two updates on a 2017 iMac in the next week.

        In my experience, the estimates for time remaining are not very accurate.

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    • #2384191

      Just installed Security Update 2021-004 on my Catalina. No issues so far.

      Although there was a small difference while running the update. Before in Mojave, the update would take place on a black screen with the Apple logo. For this Catalina update, it started with the black screen then went to a white box with Catalina logo and then back to black screen and Apple logo.

      Hope I didn’t confuse anyone! I’ll be back if something goes a stray.


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    Viewing 7 reply threads
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