micky wrote:

***Yesterday a scammer wrote him and he usually knows better, but he
called them back on the phone and they told him to install TeamViewer.
That definitely should have been a red flag but I think my brother
understands parts of the computer but not a global picture, like how bad
it would be and how unnecessary it should be for anyone other than him
and me to control his computer.

So he started on this, but stopped and called me before he finished.
We're not 100% sure that he didn't go too far, but he hadn't done at
least one last step.

If he didn't get to the point where they tried to extort money from
himeither as a ransom or a "support contract " he should ok.

Have you heard of a scam involving teamviewer

Yes. It's common. Plenty of YouTube videos of people on the phone with
them.

It seems pretty clumsy of them to limit themselves to people with the
latest version of TV. Is it so uncommon that most people don't have it
at all and have to install it anyhow when the scammers call.

Yes. Team viewer is not commonly used by your typical user.

let this be an exercise in reminding your brother and anyone else you know
to * never* trust unsolicited calls regardless of who they claim to be. The
same goes for emails.

If in doubt hang up and call the purported company yourself from a number
you have. Never call a number they give you. Also, to make sure the scanner
has dropped the line call a known number (e.g a friend) first.