How do you know when a banner comes up saying you have to notify someone for being hacked is fake?

They are all fake.

Trust your own software you installed onto your computer yourself. There is not one single outside source that knows whether or not you’ve been infected. Only the anti-virus software you installed knows what’s going on in your computer.

Edit to add: I do realize that some ransomeware will cause a banner to appear on your computer screen, so in a way, it does know what’s on your computer. My point is that it knows because it found a way to install itself. Only the things on your computer know fully what’s on it. You have to get into the computer to know what’s on it.

Here’s a further explanation.

If you are surfing the Internet, and you click on a site and a banner pops up, that is a fake attempt to get you to spend money. Close the website and surf elsewhere.

If you start your computer and you get a banner stating you must pay to have your computer unlocked, then that is ransomeware, and you’re computer has been infected. Shut down and seek a professional.

The banner got on your screen of the computer because you visited a “Sketchy Website”.

The malware doesn’t just jump up out of the ground, you have to physically go to a website and click on something on the website to get the banner popping up on your computer. Get a good free anti-malware like Malwarebytes
Don’t pay for Premium .

It might be possible that you have some kind of malware on your computer. Download Malwarebytes and run it. It’s free. It will detect malware and remove it.

Any such notification that IS NOT coming from the security software you have installed on your PC is either an ad deceptively designed to lure you into spending money on software or a virus which you can get by visiting a questionable website or as a stowaway with freeware/shareware.

If this banner has appeared more than once and is not persistently triggered by revisiting the same page then it’s the latter but in any case, I concur with the recommendation of Malwarebytes.
Though when I wanted to reinstall it on my Acer laptop after the upgrade to Windows 10 erased it, all I found was a free trial not a free version.

To anyone reading this Q, whatever you do, don’t call that number.

All of these notices are fake designed to scare you into a non-thinking panic.

I get them on my Samsung phone all the time. Annoying. Never ever had that kind of crap on an iPhone. They obviously do a much better job of screening it out.

Too bad they don’t have MalwareBytes for phones.

@Buttonstc It is not the phone “per se”; it is the Apps available on the Android, they are not vetted as well as iOS. You have to be more careful about selecting Apps when using any Android phone or tablet.

Does it necessarily have to be an app? And if so, how does one tell before installing a particular app or game?

I have an app with a very good reputation which scans every app I install.

I’m pretty sure the name of it is Outlook; it’s icon is green and black in color and depicts a shield. I’m going to double check it and everything I’ve read about it in tech sites/blogs rates it favorably.

Actually the name is Lookout. The logo description is the same.