2 Useful Tools for checking the integrity of your Certificates online:
Qualys SSL Labs
Gives your cert a score and information on how to improve the score. Remember to check “Do not show results on board.” This tool has often helped me identify TLS issues. I’ll have a detailed post on TLS issues soon.
Why no padlock?
Great tool for diagnosing certificate errors on your site. The padlock that shows your site is secure is showing up on your homepage, but maybe not on all of your subpages? This is the tool for you. It will tell you exactly what you need to do to solve the issue. It can often be as simple as changing references in your html from http to https.