How can I confirm there is no malware on my MacBook?

You touched on a point that I support. This forum is a great place to learn. I have learned so much from many of the experts who donate their time here. The link below describes how to get your old computer ready for recycle.

What to do before you sell, give away, or trade in your Mac - Apple Support

kukana2 wrote:

Apple support specifically told me “no” 3 party apps for malware checks are recommended. Now what?

This is a user-to-user support forum. If you want to restrict yourself only to Apple support, then you need to only talk to Apple support. Otherwise, they are going to be telling you one thing, and we will be telling you something else. You will annoy Apple support if you ignore their advice and do what people on the internet tell you. By the same token, you will annoy us when you refuse to follow our advice.

I don't know what you mean by "found 3 files that were suspicious". That isn't how Apple's built-in malware detection works. If it finds something, it will pop-up a dialog saying "XYZ will damage your computer". That's a bit more extreme than "suspicious". Also, it isn't even accurate. While you certainly don't want malware, it isn't going to "damage your computer" in any way. It may steal your identity, steal your credit cards, install backdoor rootlets, ransom your files, etc., but your computer will be fine.

Also, that dialog is just one part of Apple's built-in malware protection. Taken together, all of the different layers of Apple's built-in protection are very effective. However. This is a big one. Apple always allows the user to override its protections. People who regularly find themselves being tricked into installing malware can often benefit from 3rd party anti-malware protection.

Based on the evidence presented so far, you likely fall into that category. If Apple's XProtect found 3 malware files, I estimate that you have another 7 still installed. If those 3 files were installed in the first place, then you have likely overridden other parts of Apple's security and installed malware without realizing it. To be clear, this just a guess, but I usually do see multiple malware files installed. 3rd party antivirus apps are generally twice as effective as Apple's protections.

And finally, it turns out that Apple's malware removal isn't all that good. There was a significant incident a couple of months ago where an Apple security update disabled a lot of installed malware. Unfortunately, Apple's code only partially disabled the malware. Apple's bug actually damaged people's computers more than the malware did in the first place.

We have talked mostly about post-malware installation and remedies, but another important factor is prevention in the first place. Give Effective defenses against malware and other threats a careful read.

What many of us do is to download, install and run the free app Malwarebytes. It is completely safe to use and can normally remove malware. You can keep in your computer and periodically run it manually as needed. Here is a link:

Malwarebytes

There are two, and only two such titles just about all experienced users here will recommend.

Ronasara already provided you a link to one of them. MalwareBytes for Mac is free to use. It is also easily uninstalled from its own menu option when you're done with it.

The other is EtreCheck. This is also free to use. It's main purpose is to take a snapshot of your system. What type of hardware you have, and what software is running. After running the scan, you copy the report here so other members can see it. All personal information is automatically redacted by the app. It has been used, easily, thousands of times on this forum.

All I can say is that Malwarebytes has never caused a single problem to best of anyone's knowledge here. When it comes to antivirus apps, that is a whole different story. They all will definitely slow down your computer and they will often cause other problems as well. I would not recommend it if I don't use it myself. You have to decide for yourself.

kukana2 wrote:

I plan to buy a new computer and concerned my old computer may have malware still on it. How can I make sure it is clean? I assume to use both apps you recommended to scrub it. Thanks again!

There is nothing you need to do to the new computer. When you first turn it on, it will be free of any malware.

If you don't remove the malware from the old computer, you will not be able to restore your data to the new computer. You would need to setup your account from scratch. You can sign in to your iCloud account, but that is as far as you can go.

https://discussions.apple.com/thread/252743624

See my response here, and if you get any info, please reply below.

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