Joey10594 wrote:
Since updating to Big Sur, none of my downloads will open (both new and old/predating the update). It's not a security issue, as I already have "allow from AppStore/identified developers" checked.
Every download/attempt to open a file results in a "(name) is damaged and can’t be opened. You should move it to the Trash" with the options to trash or cancel.
Not sure what's going on. Any advice?
Verify you have rebooted more than once since upgrading the macOS.
Boot into Internet Recovery (Option Command R) and from the dropdown menu: Utilities> Disk Utility> run the First Aid on your Macintosh HD (and the "Macintosh HD-Data" volume as well if Catalina/Big Sur) If errors are found and repaired, run again until no errors reported.
Disk Utility>View>Show All Devices The best sequence is —
• Volume level
• Container level
• Parent drive
Recovery: https://support.apple.com/en-us/HT204904
To trouble shoot further you can:
—Try a 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 test. Reboot as normal and test as caches get rebuilt.
In Safe mode third party system modifications and system accelerations are disabled, it removes malware, etc hampering smooth operation, however a reboot will put it back to normal mode.
This test will tell you if third party interference; extensions etc are not loaded in safe boot mode.
—Test issue in another user (or guest user) account https://support.apple.com/guide/mac-help/set-up-other-users-on-your-mac-mtusr001/mac
This will tell you if it a universal issue or isolated to your user/admin account.
Uninstall all third party apps that are Cleaners/Optimizers/VPN/Anti-Virus