10.15.3 And 10.15.4 Software Updates Won't Install

MartinL-R wrote:

When I go to settings and click on "install now" in the software update preference it asks to be restarted. It shuts down and the apple icon appears with the loading line underneath. It only last for a few seconds and the install goes really fast. I write in the password on the lock-screen and open the mac, and then the installation hasn't been install. No warnings or system failure, but I need to do the whole process over again and it never gets installed.

Any tips or solutions to this problem?

I downloaded the updates it self for a few months ago.

You do not say what exact Mac /model /year /size /retina /TouchBar is this

or

what exact macOS you are currently running?

Delete and empty the trash any old installer.

If you are currently running a version of macOS 10.15.x then download directly the Combo update macOS 10.15.4 https://support.apple.com/kb/DL2037?locale=en_US

If you have issues running this, reboot into Safe boot mode and try again, installing the combo.

SafeBoot https://support.apple.com/en-us/HT201262

Takes noticeable longer to get to the login screen, does a 5-15 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc. Login and launch your update.

MartinL-R wrote:

It's a Macbook Pro Retina 13" from late 2012 and runs 10.15.2 Catalina. Normal TouchBar - Keyboard version.

Would it maybe help if the dowloaded installation would be deleted or removed so the updates could be downloaded once again if that's possible?

yes this is what I tried to say above.

Download the Combo.

MartinL-R wrote:

Thank you so much! It didn't work with the Combo version only. Had to install it in Safe Mode for the updates to be installed.

Good computing MartinL-R ! Thanks for the feedback.