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Firefox will not open a site because it thinks it is not trustworthy, but it has previously done so.

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When I try to open a previously trusted site to make an appointment on line with my doctor Firefox says that it is not to be trusted. I then used IE to go to the site and it allowed me access. Please can you advise me as to how I can overcome this problem. I have tried different things from your help pages but there are too many alternatives and it becomes confusing. This is the error message:

www.tramita.gva.es uses an invalid security certificate. The certificate is not trusted because no issuer chain was provided. (Error code: sec_error_unknown_issuer)

When I try to open a previously trusted site to make an appointment on line with my doctor Firefox says that it is not to be trusted. I then used IE to go to the site and it allowed me access. Please can you advise me as to how I can overcome this problem. I have tried different things from your help pages but there are too many alternatives and it becomes confusing. This is the error message: www.tramita.gva.es uses an invalid security certificate. The certificate is not trusted because no issuer chain was provided. (Error code: sec_error_unknown_issuer)

All Replies (3)

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You can retrieve the certificate to check who issued the certificate. You should always do that to see if that helps to identify the problem (missing intermediate certificate or something else).

  • Click the link at the bottom of the error page: "I Understand the Risks"

Let Firefox retrieve the certificate: "Add Exception" -> "Get Certificate".

  • Click the "View..." button to inspect the certificate and check who is the issue.

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If you can't add an exception, but get a pop-up with the error message then you can check the pref browser.xul.error_pages.enabled on the about:config page and make sure that the value is set to the true (default).

See http://kb.mozillazine.org/about%3Aconfig

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Unfortunately, the link at the bottom of the error page: "I Understand the Risks" is not visible. So I cannot click to accept the risks

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can you try to remove the old certificate/exception for this site in firefox > options > advanced > encryption > view certificates > servers & see if it's working afterwards?