Since updating Catalina 10.15.7, Safari will not open.

Hi there, boulderssite.

It appears that you're having a problem with Safari after update your Mac to macOS Catalina 10.15.7. It simply won't open when you select it, and we're glad to help with this.

Use Screen Time on your Mac - Apple Support -- If Screen Time is turned on, make sure that Safari hasn't been blocked.

How to use safe mode on your Mac - Apple Support -- If Safari hasn't been restricted, restart your Mac in safe mode and see if Safari open. Depending on whether or not it does, use the additional steps below (if a step instructs you to reinstall, select the contact Apple Support link near the bottom):

"If the issue continues in safe mode

If the issue continues while in safe mode, or your Mac restarts several times and then shuts down while starting up in safe mode, you should reinstall macOS and make sure that your Apple software and third-party apps are up to date.

If the issue doesn't continue in safe mode

If the issue doesn't continue while in safe mode, leave safe mode by restarting your Mac normally. Then test for the issue again. The issue might be resolved.

If the issue returns after leaving safe mode, startup items are probably at fault. Apps can install such items in numerous places, and they aren't always easy to find or recognize. For that reason, you should first make sure that you've installed any available updates for your Apple software and third-party apps.

If updating your software doesn't help, try any of these solutions:

• Test your login items.
• To learn whether software in your user account is causing the issue, set up a new user account, then log in to it and try to reproduce the issue in that account.
• Unplug all accessories from your Mac, including printers, drives, USB hubs, and other nonessential devices. You could have an issue with one or more of those devices or their cables.
• Reinstall macOS.

If you still need help, please contact Apple Support."

Take care.