I am doing dialectology, and I was trying to install QGIS 3.12 (and QGIS 3.10 before) to use it in my study. Every time I opened the software my Mac always showed this notification "QGIS 3.12 ( QGIS3.10) can't be opened because Apple cannot check it for malicious software".
I also tried installing Python 3.8 hoping it would work, but it didn't and I received the same message above.
How can I install and use the software so that I can start learning the software?
After you try and open QGIS and get the error, you need to open MacOS "System Preferences" and select "Security & Privacy". Click "Okay" to dismiss the error, and you should now see an option under "General" to run the program below the "Allow apps downloaded from:" section.
After installing QGIS 3.36.2, I got the error message "QGIS.app cannot be opened because the developer cannot be verified." In MacOS Ventura 13.5.2, I opened System Settings, Privacy & Security. Under Security, I was able to allow QGIS to open.
On QGIS Official download website, they actually acknowledge this MacOS-related security issue, and just like you, I actually ran into it.
This is the working solution, recommended from Apple Software Support.
1. Launch the `Settings` app on your Mac.
2. Select `Privacy & Security`
3. Scroll down until `Security`
4. Under security you'll see two radio buttons under `Allow applications downloaded from` ensure "App Store and identified developers" is selected.
Below it, you will see a message about QGIS that you'll need to approve (by adding your password or passkey fingerprint).
Ahaa!, QGIS Will automatically launch.
