The connection has timed out The server at apus20.cert.fnmt.es is taking too long to respond.

For https://apus20.cert.fnmt.es/

I get an error page which has the following under Technical Details:

apus20.cert.fnmt.es uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported.

(Error code: sec_error_unknown_issuer)

Is that what you see?

This is not related to either:

• Blocklist for bad add-ons (you can re-enable that)
• Phishing/malware list for bad sites (you can re-enable that if you disabled it)
• Permission to install software under Preferences > Security (you can remove the exception)

This is related to a problem with the website's SSL certificate. The problem is that the website's certificate was not signed by a recognized certificate signing authority and therefore cannot be verified as being the real certificate for that site. And this leaves open the possibility that the address is being directed to another site which could steal your information.

I know you say this address is one you have used before, but Firefox is telling us that the server responding to that address did not prove it actually is the correct server.

When I try to visit that address in Google Chrome, I get redirected to this page: http://www.cert.fnmt.es/

This does not look like a tax authority to me, so I'm confused about what is going on. Could you double-check that you are visiting the correct site?

Tks for your time. Correct, that is what I see Try to tell what could have happened: With my old Mac, I used a kind of certificate to taxdeclaration. FNMT was/is the issuer for the certificate. The old Mac crashed (is now in the scrap yard). I managed to transfer all my files, programs to my new Mac. Old Mac used a old version of Firefox for the FNMT certificate. I had to update the certificate with the new Mac so I had to cancel the old certificate. Before I canceled the certificate, I used the FNMT and the website without being blocked. Could it be that when I cancelled the old certificate, I have also authorize Firefox he blocking? To do the certification (several steps) and during the process ( https://www.sede.fnmt.gob.es/en/certificados/persona-fisica/obtener-certificado-software), I cannot modify browser etc.

If you check your Certificate Manager, do you still have the certificate you obtained before?

"3-bar" menu button (or Firefox menu) > Preferences

In the left column, click Advanced

On the right side, click the Certificates mini-tab if it is not already selected

Then click the "View Certificates" button to open the Certificates Manager and check the "Your Certificates" tab to confirm that your new certificate is there.

If you have both, then try removing the old one in case there is a conflict -- in other words, Firefox sending the wrong certificate.

The My Certificates disappeared. Same goes for the certificates from the issuer/manager, also gone! I e I do not have any kind of certicates with FNMT

The server seems to be sending a self-signed certificate,

• http://www.networking4all.com/en/support/tools/site+check/report/?fqdn=apus20.cert.fnmt.es&protocol=https
• https://www.ssllabs.com/ssltest/analyze.html?d=apus20.cert.fnmt.es

cceder said

The My Certificates disappeared. Same goes for the certificates from the issuer/manager, also gone! I e I do not have any kind of certicates with FNMT

When you obtained the certificate, did you save it somewhere convenient? Can you import it again? If it certificate is in the Mac keychain, there might be a way to export it from there and then import it into Firefox. (I am not very familiar with this procedure on Mac.)