"Content was blocked because it was not signed by a valid security certificate" error shown when opening form in IE11

Can you please tell us what is the link to the form - or the link that your clients and you are using to access the same so that we can check it out and look into what is causing this issue?

The form is embedded in our intranet.  When the user clicks submit, it looks like the link is https://submit.jotform.us/submit/51876025024148    The form has been working for several months; the first report we had of anything wrong was yesterday. 

If your users are redirected to that link, then the form has been successfully submitted, and you should be able to find it in your submissions page.

Have you checked if there is an extension blocking the link?

It could be something that does not allow to submit your form.

Have you recently installed an app to your PC? 

Know that would be helpful for us to find what is causing the issue.

Thanks for your reply.  When the users click on the submit button, the error message appears instead of the Thank You message.  When I check Jotform website, the submission does not exist.  I am not using extensions.  This issue happens on all PC's.  The only change we've made recently is upgrade from IE 9 to IE 11.  No apps have been added, changed or deleted.  Does form submission require that cookies be enabled?  Is there some setting in IE 11 that needs to be enabled or disabled? 

I just tested your form, and it was successfully submitted. Have you tried it outside the intranet?

Link to your form: http://www.jotform.us/form/51876025024148 

I think the issue might be related to your IT department security configurations.

We are the I.T. department here!  Is your certificate out of date?  That error message is the message we get when a web site's certificate's is out of date.  According to IE 11 help, the certificate at https://submit.jotform.us  must match the exact website and apparently no longer does. When you tested the form, did you use IE 11.9600.17843?

No, the certificate is not out of date. It is valid until 2016-10-06, so it is OK for several more months.

You can check the certificate yourself as well if you check out the form directly: https://form.jotform.com/form/51876025024148

If you check the certificate you can see that it is a multidomain certificate, covering (amongst others: submit.jotform.us) so there should not be such error.

Now, I understand that the issue is on your intranet, but can you please tell us if you are able to recreate this issue on all devices in the same or only on some devices?

I presume that there might be few devices that have wrong date and time setting on their devices set - since as you know certificates have start and end date, so it might be showing right time, and right day for them, but wrong year - which would cause such issue (this is just a guess without seeing the issue).

Also, what happens if you access the link above directly in your browser that experience issue on your intranet, and finally, the intranet should have access to web in order to create a submission. If there is no internet connection available, it will not be able to submit the form - which it could still show it if the source code embed method is used.

Since you say that you are in the IT department, then I would also suggest checking out if you can see any redirect policies being applied in order for submission to be able to access the internet (I presume here that you have access from intranet to outside world). Then if such polices exist, it would be good to check them out, since if some endpoint is used to go out, it might be seen as not valid point - due to certificate check.

In such case submitting the form without HTTPS protocol should work without any issue (you just remove the S from it and the form will still work, just without certificates).

We're making some progress.  We discovered that if we EMBED the form in a page on our intranet, we see the issue.  However, if we LINK to the form directly we do not see the issue.  So the certificate IE 11 must be complaining about is either OUR certificate on our intranet, or the IE 11 settings.  Since this issue did not exist before we upgraded to IE 11, we assume now it's an IE 11 issue.  We tested with Chrome, both EMBED code ad LINK and both work fine from our intranet, so we're very sure it's an IE 11 issue.

Great to hear that :)

It might be possible that IE 11 does not check the certificate fully - for example, that it had trouble checking the certificates values for some resources, causing it to fail in such manner.

If you still wish to use the page embedded on your website, feel free to try using non https embedded code, which should resolve this issue as well (as everything should be loaded over HTTP at that point).