Using Mac OSx10.10.5

Perhaps due to Safari having been obsoleted or lacking current updated secure certificates?

Usually these messages and associated reasons can be superseded through a newer macOS.

And depending on the age and vintage of your Mac, its upgradability can be known.

• How to get old versions of macOS - Apple Support

https://support.apple.com/en-us/HT211683

I've asked the Mods to move the other user who hijacked your thread elsewhere. Sorry, that happens.

That error message indicates a problem that started in Sept when one of the biggest vendors of security certificates replaced the cert that worked fine with old, out-of-date browsers and OS version with one that would not work with any old gear. You cannot change that.

Ref: https://letsencrypt.org/docs/dst-root-ca-x3-expiration-september-2021/

We cannot give you a precise answer on how to deal with this without knowing what year model Macbook Pro you have. That affects the max OS you can have, which, in turn, controls which browsers may still work with obsolete OS versions. Please do "About this Mac" and tell us your sub-model, the part with a year, as in this example:

You are not maxed a sOS 10,10. Just about any Mac running 10.10 should be able to run at least 10.11 which Chrome—for now—still supports. Firefox now requires 10.12. Still, our knowing your sub-mail will let us show you exactly what can or cannot be done without posting a lot of generalities.

Be aware that you are seeing the handwriting on the wall. You will be juggling workarounds for another year or so until your computer won't connect with any browser.

..arichmond1234:

Perhaps some 'secure certificate expiry' and other

out-dates are loitering behind that billboard?

I have the latest update and it happens when I use chrome, safari and even Incognito.

what model-year MacBook Pro 13-in ?