Hello, when performing the task of "empty trash" the following message box persists forever so that I have to kill it. After killing it, I always see that the trash bin is empty. How can I make the message box go away?

Give this a try: boot into Safe Mode according to How to use safe mode on your Mac and test to see if the problem persists. Reboot normally and test again.

NOTE 1: Safe Mode boot can take up to 3 - 5 minutes as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

NOTE 2: if you have a wireless keyboard with rechargeable batteries connect it with its charging cable before booting into Safe Mode. This makes it act as a wired keyboard as will insure a successful boot into Safe Mode.

The Files that are in the Trash Bin were locked where ?

Were they located on the computer ?

Were they located on an External Drive.

If on the External Drive, was that Drive used for Time Machine Backup purposes ?

Was the User attempting to Delete Snap Shot Off the Time Machine Drive ?

If Yes to above, shutdown the computer with the Drive still attached.

Disconnect the Drive and restart the computer

Does the issue stop ?

Boot into the Recovery volume (boot with the Command + R keys held down  - Intel Macs) or  (How to Boot an M1 Mac into Recovery Mode), select Disk Utility and run First Aid on all available volumes. Reboot normally and try trashing again.

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