macOS 10.15.7 - what does the last Catalina update bring before Big Sur?

macOS Catalina 10.15.7 update

Last night Apple threw an update for your Mac into the ring, which mainly focuses on bug fixes. At the same time, an update for iOS (version 14.0.1) is available, which is also a typical bug fix update. I think no further updates should be expected with macOS. The next then is the big upgrade to macOS Big Sur.

Update: 28.09.2020/XNUMX/XNUMX: Update causes massive problems with some systems

My reader Simon (thanks!) Pointed out to me that this security update can cause problems. Most of the time such updates go smoothly, but in this case there seem to be some users who have had quite a few incidents with the system after the update. Here is a small list that I am at Mr Macintosh have found:

  • Memory issues - Reports of large increases of memory usage = no free memory and a large amount of compressed memory.
  • Slow boot & high fan speed
  • System slowness / stalling in finder
  • New local users cannot be created through Users & Groups.
  • Migration assistant crashes to login window when started.
  • Large amounts of system.log entries - Class asn1SetToken is implemented in both /System/Library/PrivateFrameworks/StoreServices.framework/Versions/A/StoreServices
  • Errors when using tmutil localsnapshot /
  • Error when running softwareupdate -l (not sure if it causes any issues with the software update binary)
  • System locks up in Desktop & Screen Saver> Screen Saver when trying to select a picture type screen saver.
  • WindowServer Process using 4 times amount of memory. Should be anywhere between 40-125MB after the update it jumps to 400MB
  • cDock 4 - Dock customization app becomes unusable.
  • Menu bar sometimes does not change after switching from applications back to the finder.

At this point, perhaps, a few reading tips on the new Mac operating system:

Shortly after the release of macOS Big Sur, I will have one again Collective contribution with problems and solutions for the new macOS. But for that it has to be published first ...

The update to macOS 10.15.7 should be installed in any case, as it is a security update.
The update to macOS 10.15.7 should be installed in any case, as it is a security update.

Fixed problems with WiFi and iCloud

Apple itself reveals the following additional information with the update:

macOS Catalina 10.15.7 update –– restart required

macOS Catalina 10.15.7 provides critical security updates and bug fixes for your Mac.

  • Resolves an issue that prevented macOS from automatically connecting to wireless networks
  • Fixes an issue that could prevent files from syncing through iCloud Drive
  • Corrects a graphics issue that could occur on iMacs (Retina 5K, 27 ″, 2020) with Radeon Pro 5700 XT

Some features may not be available in all regions or on all Apple devices. More information about the security content of this update is available at:

The probably last update for macOS Catalina has been delivered by Apple since yesterday.
The probably last update for macOS Catalina has been delivered by Apple since yesterday.

Mac: no WiFi connection to the router

The WiFi issues that are being addressed here relate to the fact that some Macs refused to reconnect to the router when, for example, they woke up from sleep. I had received such messages from readers recently and in some cases we were able to fix them by setting the wireless network to 2,4 GHz or 5 GHz. The solution is here in the post described in detail.

iCloud bug also fixed

According to Apple, the update should also fix a problem with iCloud synchronization. I very much hope that this is also about the iCloud Photo Library, because in the past few weeks it has very often refused to sync new photos from the iPhone. Only a restart helped me here, but this only solved the problem temporarily.

It would be desirable if the update provided more reliability in this context.

Security update included

As I read at Heise, macOS 10.15.7 also offers a fix for four security-related bugs, known as Model I / O, Sandbox and ImageIO, that allow attackers to execute code.

For the older macOS versions High Sierra and Mojave, these gaps are also closed with security updates.

As a rule, the Mac itself informs you about the upcoming updates.
As a rule, the Mac itself informs you about the upcoming updates.

Where can I find the update?

If your Mac doesn't notify you of the update with a notification, you can go to System settings> Software update install yourself.

If you select this point, the Mac will automatically search for new updates and should display the macOS Catalina Update 10.15.7.

The update is started via the system settings and the item "Software update", which should show a red one as a batch.
The update is started via the system settings and the "Software update" item, which should show you a red one as a batch.

My recommendation: install with caution!

It sure sounds silly to some tech-savvy people to give a recommendation here, but I have some readers who have little to do with computers and who ask me whether or not to install the XYZ update.

While I always recommend backups and a little patience for major updates (like the coming one on macOS Big Sur), you can assume with this update that the Mac will not cause any problems afterwards. On the contrary: It is a bug fix update that is not aimed at new features, but rather fixes existing problems. For this reason I install such updates as quickly as possible.

A reader just wrote me that he got massive problems with the update and spent a day recovering data with the TimeMachine. Other people also seem to have run into problems with the 10.15.7 update, like this post here shows. For this reason, I have to withdraw my first recommendation to install the update directly and would say that you should do a 1: 1 backup with Carbon Copy Cloner, Super Duper or Smart backup should do.

Everything went smoothly for me with the macOS update ... I hope there are no complications with you either.
Everything went smoothly for me with the macOS update ... I hope there are no complications with you either.

The update requires a reboot, but my Mac booted cleanly after the update and so far I have not seen any negative effects.

You are welcome to leave a comment here and write whether something strange has occurred to you.

Did you like the article and did the instructions on the blog help you? Then I would be happy if you the blog via a Steady Membership or at Patreon would support.

8 Responses to “macOS 10.15.7 – what does the latest Catalina update bring before Big Sur?”

  1. Good morning,
    unfortunately I relied on your recommendation - 10.15.7 seems anything but the ultimate update :-(
    Look here :

    It cost me a day with my ™ :-( and I wonder if I'm the only one who had problems with the Timemachine after the update to 10.15.7. Everything was fine right after the update. I usually ask for an update the time machine off for 1-2 days. After I activated this, the problems started with me. TM starts the backup of 7GB. After 3,5 GB it got stuck. Instead, the mds_store process starts with 100% utilization. I read that run like this overnight. The next morning unchanged (TM at 50% mds_store-Process 100%). So I had to cancel TM and delete the inprogress folder. Then I rebuilt the Spotlight index and now I ran to TM again. Hope let's see that everything is now running smoothly again.

    1. Hakllo Simon! Oh ok! Thanks for your contribution and the reference. I wasn't aware of that yet. But I'll include it in the article right away so that other readers know. I will limit my recommendation accordingly. Sorry for your time. :-(

  2. Hey Jens no problem-thanks for your blog and the useful information, as well as your direct integration of new information !!!!

  3. Hello Jens, a little late due to my vacation, I am giving feedback on the last update Catalina 10.15.7. We have a MacBook Pro and Mac Air, which I always keep up to date, unfortunately also with this update. Since then, both devices have had very loud fan noises and the hardware gets warm even though no programs are running in the background. I tried all the tricks described, but there was no improvement. Now I hope that Apple will correct it soon. Question: Where can you easily complain to Apple about such errors? I think if a lot of users get in touch, it goes faster and the problems are taken seriously. Wish you a good start to the week.

    1. Hello Erich! The good news: Apple apparently re-released the 10.15.7 update yesterday. You should then install that over it and the problems should be resolved. In theory ... but what I've heard from other users so far, the ghost actually stops afterwards. Have a nice week too.

  4. Hello everyone, I updated my MacBook Pro yesterday. All my files in a folder - that were in the Documents folder have ended up in a security area ... with the note, for security reasons! And I can no longer push them there either. Moving is not possible either. Now copy of the folder with my files copied to the desktop. Find no explanation or hint on the net. I do not understand that. Has anyone had the same experience?

    1. Hello Tatiana! Oh, some other reader had the same problem. I just don't know what the solution was now. Maybe restart, then hold down CMD + R. Then install Catalina over it - nothing will be changed in your data. And then restart the Mac. Maybe then it will work. Otherwise I can't think of where it could hang. If someone else has a tip, please contact us! : D

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