Issues with the Norton 360 for Mac file cleaner.

Any Third Party Applications that will interfere with the normal operation of the OS, alter, modify, remove or delete or attempt to do so is an invitation for disaster and comprising the Operating System

It may require a Reinstallation of the OS in-order to replace any modified, altered, removed or corrupted elements of the OS this software has inflicted on this computer 

Although some or all of these Applications maybe or may not be available on the Apple Apps Store, it does not mean Apple has verified what exactly the Application can do, does do or is doing to the Computer. That responsibility is left to the User to perform their due diligence on the Application before purchasing and installing it.

Any of the below should be removed as per Developers Instructions 

This will include CleanMyMac , MacKeeper

This will included Norton Antivirus ,

The The Built in Security  is all that is required.

A User can find most anything on the Internet.

It does not mean it true and accurate either

since the user ( you ) has such a long time using Apple Produces does not necessarily mean they truely understand the Under pinning of to macOS which is based on the Unix foundations

You need to consider the Monterey operating system.

It is installed only with an Apple certified installer from Apple certified servers. The operating system is on a sealed volume that the user cannot even modify, to all users it behaves as read only. It is physically impossible to insert a virus in such an operating system.

That said, you can certainly install malware in your browser or some other user accessible part of your Mac. But those are mostly annoyances and easily avoided by using common sense and/or utilizing a well trusted program like Malwarebytes.

As you have found out, the cure can be worse than the disease.

On Catalina you could allow an application to alter system space at install time. Bad idea with an application that AT BEST guesses what parts of the OS are necessary. Monterey even cuts off trusted software like CarbonCopyCloner from changing the "sealed encrypted volume" to prevent any non Apple software from modifying the system.

...it threw well over 100 files into the trash (mp3s, pdfs, word docs, text files, file extensions, etc.). Only about 8 files were actually duplicates, and maybe 3 file extensions were orphaned.

This tells you all you need to know about this product. It's dangerous and risks dataloss.

I called Norton Tech support, who told me that Mac users only use the Norton file cleaner when they want to get rid all the files on their computer, and that you aren't supposed to use it if you want to keep your files!

This tells you all you need to know about this company.

I opted for Norton because Macworld, Mac User, PC World, CNET & similar sources rated it highly - although not one single review identified a problem with the file cleaner.

And this tells you all you need to know about these sources of information - all of whom heavily rely on advertising from the very same companies whose apps they review - now how do you think that's going to go?

Delete the app and remember: Never install any app that claims to "tune up", "speed up" or "clean up" your Mac. These apps exist for one reason: to separate the unwary and inexperienced user from their hard-earned money. At best they do very little, at worst, they can damage your OS installation and cause far more problems than they "solve".

There has been sufficient advise offered, from more than one Contributor, for the User to make an informed and educated choice what the next course of action is required.

The suggestions have been put forth on a volunteer basis, in good faith and in the best interests of the computer.

I do believe I started using Macs the same year as you, and if that's the case then

the days when Norton was actually a reliable and useful product.

that will have been in OS9 days...

The rule of thumb is to not install any anti-virus, or so-called App or file cleaners on macOS. You are just asking for problems as years of posts have demonstrated.

You can search these communities to read the hundreds of posts from users who have observed negative results from using third party apps that claim to protect, clean, boost performance, etc.

Norton is the last app I would use in this category. I had nothing but issues with Norton products from years ago.

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