Unable to open Security & Privacy preference pane

Hello Blanzat Bob,

Thanks for asking the Apple Support Communities for help with loading the Security & Privacy Preferences on your Mac. Also, thanks for the info about the troubleshooting you attempted already.

Since the same issue occurs in safe mode, I recommend testing if this occurs in a newly created test administrator user or not. I am aware the issue is not occurring in the Guest user, but this account is not the same as other admin accounts.

To set up a test user, please check this help article: How to test an issue in another user account on your Mac - Apple Support

After you are done testing, please check the section related to results, titled "If the issue happens in the other account" or "If the issue doesn't happen in the other account” for the next troubleshooting steps. Thanks and have a wonderful day.

Hello Blanzat Bob,

Thanks for trying the troubleshooting provided. Since the issue is also occurring in the test user, I recommend reinstalling macOS.

How to reinstall macOS from macOS Recovery - Apple Support

Thanks and have a wonderful day.