by loren_d_c » Wed Aug 19, 2015 1:39 pm
If there is an SSL cert being used for a page (and all objects like images, css files, and js files on the page also use a valid SSL URL) and you are still getting SSL security errors/warnings from browsers, then it is possible that the SSL cert was creating using SHA-1 encryption and expires sometime in 2017. SHA-1 is an older encryption no longer considered secure by most current browsers (at least Chrome, Firefox, and Opera, I'm not sure about IE), and any SHA-1 certs that expire too far out in the future are now getting this warning. For more on that see:
https://konklone.com/post/why-google-is-hurrying-the-web-to-kill-sha-1
If this is the case, and your host is unable to install a new SHA-2 based shared SSL cert on their hosting server where your site is located, then that probably means that even if you buy your own SHA-2 certificate they probably wouldn't be able to install it on that server either (although you should verify that with them first). In that case, your only solution would be to move to a different server that can support SHA-2 certificates. So you could ask your host if they have newer or different servers that they could move your site and store to that would support the newer SHA-2 certificates, whether it be one of their shared ones or one you purchase.
-Loren