Can't connect to zoom only on one computer

[funkfly]

Hiya -

I have a bunch of devices at home, all connecting to Zoom without a problem. Smartphones, laptops, PCs and Macs, Androids and iPhones. No problem.

I have an old iMac which I set up for my kids last year (during the lockdowns) - everything worked fine.

Recently my kids had to be isolated again, and now, for some reason, Zoom is not working on their computer.

Not only the zoom app, but I also can't connect to zoom.us on any of the browsers installed on this computer.

I tried connecting from the kids' account and also from my own admin account, and still nothing.

All other devices are still able to connect to zoom without issues, and I also checked the computer for firewall/proxy settings which might be suspicious, but found nothing.

What am I missing here??

Thank you for your help!