Insecure response error with HTTPS on remote computer

Question

I have following problem with HTTPS. My client navigated to checkout page and he did not see any content. Checkout site is rendered on HTTP protocol but most of content is loaded dynamically through SSL (for example js files used to render cart content). And this content was unable to load because of net::ERR_INSECURE_RESPONSE.

Below you have screenshot of console (Chrome). As you can see every secured request failed (even one from AmazonWS) so I assume that problem isn't related to server/scripts but rather browser or internet configuration. Also when client tried to access page via private browsing he suddenly succeded. Does anyone have idea what could be wrong? Just to add, certificate is still valid (to 2016.01.16).

Answer 1

Load the script directly in your browser. Look at the detailed security information it gives.

They certificate is using an obsolete encryption method.

Answer 2

I had the same issue when Fiddler was running on the background. Try closing Fiddler.

[Edit]

I had set the option to decrypt HTTPS sessions by re-signing traffic using self-generated certificates in Fiddler.

If your client wasn't using Fiddler at the time, could it be that traffic goes through a proxy where another certificate is used in the middle?