Firefox Community Forum

Google stopped working for me in Firefox a couple of weeks ago. Every time I enter something in the Google search bar, I get the following error message:

An error occurred during a connection to misho.sodirant.com. SSL received a record that exceeded the maximum permissible length.

How can I fix this? I have had to switch to Chrome to Google anything. I want to stay with Firefox since all my bookmarks are there.

David Beaverton OR

Доброго времени суток.

Я установил сертификаты по инструкции, которая лежит на s.sber.ru/70VQ2B . После этого не прогружается полностью окно входа на online.sberbank.ru (не видно содержимого фреймов). Проблема полностью аналогична описанной здесь: https://support.mozilla.org/ru/questions/1597415

Firefox ESR115.40 (64-разрядный, Windows 7) - страница выглядит, как на скриншоте по ссылке выше.

Установлены скачанные сертификаты в самом браузере, они отображаются в разделе Управление сертификатами -> Центры сертификации. После этого абсолютно ничего не изменилось.

Может, надо еще что-то сделать? Или на Firefox ESR115.40 вообще работать не будет? До перехода на сертификат от Минцифры России проблем не было.

Hello Mozilla Support, I am getting Error 526 when I try to open YouTube in Firefox. Other websites work normally, but YouTube does not open. I have already checked my internet connection and restarted Firefox, but the problem still exists. Please help me fix this issue.

Secure Connection Failed

The page you are trying to view cannot be shown because the authenticity of the received data could not be verified. What can you do about it?

The issue is most likely with the website, and there is nothing you can do to resolve it. You can notify the website’s administrator about the problem.

Error Code: PR_CONNECT_RESET_ERROR

this is the entire error message.

Hi, I try to use Firefox for my job and faced with the problem that I can't open state owned website due to sertificate signature error. I ready to take a risk but I can't find the button "Proceed.. (Risky)". This button simply not showing. In th same time in mobile version I saw this button, could take permssions myself and open the website. I tryed to add root and sub sertificates of the Goverment, tryed to add the site address to exclusions -- all these steps don't work. I can't open the site and can't find button "Proceed.. (Risky)". Moreover, in the same time, I can open this website without any questions and problems with Safari and Chrome.

I use the last Firefox version (153.0) from Firefox official website.

How can I resolve this problem in Firefox? Please help me

‘Firefox is blocking me websits or torrent sites because the certificate is outdated I have no option to carry the risk an acces it!!!’ This is disgusting!! Many good websites habe no certificates. It is obviously used as censorship. What can I do? I used the Testa del Rutor terrent

Got this error: Your connection may not be private An app or service may see your encrypted traffic from this site. Learn more

Now I know what may be causing it but you offer no solution.

Over and over again when I try to open a website I get the notice that says "Secure Connection Failed". I have to restart my laptop and then I can open the website that I tried to access before. I've tried using the suggestions in the forum with no result in solving this problem. I've attached the page that comes up showing the problem.

Since I updated a week ago I keep getting a warning of a bad site on sites that I know and trust. The problem is www.ui-deref.com Any ideas how to correct this?

I am currently unable to access certain websites, particularly banking sites. The following error appears: Secure Connection Failed

An error occurred during the connection to modern.ttbank.ir. The peer's certificate has been revoked.

Error code: SEC_ERROR_REVOKED_CERTIFICATE

   The page you are trying to view cannot be displayed because the authenticity of the received data could not be verified.
   Please contact the website owners to inform them of this issue.

This is happening even though I was able to access this site without any problems until yesterday.

I get several message that: I cannot connect to Amazon, Several websites, etc. It sometimes has something to do with private windows and/or can't connect! Could be license, ssl, etc. When I force a firefox private window, it works for a while then goes back to the same thing. Any ideas how I can fix this?

I keep getting: "Your connection may not be private Learn more. The page isn’t redirecting properly Firefox can’t connect to the server at auth.www.abebooks.com." I believe that I followed your instructions, but I'm not sure. I do not understand why "auth." appears in the Mozilla response when I do not type "www.auth.abebooks.com" but simply "www.abebooks.com." Thank you! Claude Gratton

I periodically need to access a website with an expired or self-signed certificate. I understand the risks, but the browser won't let me. I've searched both the regular settings and about:config, but I can't find an option to restore the button to ignore the warning. How can I ignore the SEC_ERROR_BAD_SIGNATURE notification and proceed to the website I need?

After updating software and restarting my laptop (Lenovo running windows 10 or 11) Firefox now displays this message for every web page (this example from attempting to access Gmail, but same message with all other sites I have tried):

"Be careful. Something doesn’t look right.

Firefox spotted a potentially serious security issue with mail.google.com. Someone pretending to be the site could try to steal things like credit card info, passwords, or emails.

mail.google.com has a security policy called HTTP Strict Transport Security (HSTS), which means that Firefox can only connect to it securely. You can’t add an exception to visit this site."

I now can't access any pages using Firefox. Long term user, so I hope you can help me! C

I was going to look at a friend's website that has an SSL-certificate, has had it for years, which has been working all that time. Now Firefox informs me: "Firefox doesn’t trust this site because its certificate isn’t valid for www.wuwei-school.nl. The certificate is only valid for: wuwei-school.nl."

Really? I pretty sure there's nothing wrong with the certificate and I was taught that the "www" component is not important as a prefix for the domain name in a URL. It is just a shorthand code to show that the address is a URL. Can Mozilla fix this issue? Or, at least, explain?

Thanks

Firefox's full message: - - - Be careful. Something doesn’t look right.

Firefox spotted a potentially serious security issue with www.wuwei-school.nl. Someone pretending to be the site could try to steal things like credit card info, passwords, or emails. Advanced What makes the site look dangerous?

The site is set up to allow only secure connections, but there’s a problem with the site’s certificate. It’s possible that a bad actor is trying to impersonate the site. Sites use certificates issued by a certificate authority to prove they’re really who they say they are. Firefox doesn’t trust this site because its certificate isn’t valid for www.wuwei-school.nl. The certificate is only valid for: wuwei-school.nl. What can you do about it?

Probably nothing, since it’s likely there’s a problem with the site itself. Sites use certificates issued by a certificate authority to prove they’re really who they say they are. But if you’re on a corporate network, your support team may have more info. If you’re using antivirus software, try searching for potential conflicts or known issues.

View the site’s certificate

Learn more about secure connection failures

Error Code: SSL_ERROR_BAD_CERT_DOMAIN

Aug 21, 2026 11:10:31 PM GMT+2 - - -

Subject: Persistent “Secure Connection Failed” after SSL certificate was re-issued – cannot clear cached certificate Hello Firefox Support, I am experiencing a persistent SSL certificate problem that only occurs in Firefox. Background

Domain: j3tourshongkong.com (and www.j3tourshongkong.com) The domain was recently moved to a redirect service (redirect.pizza) A new valid SSL certificate was issued by Let’s Encrypt via the redirect service The certificate is confirmed working by the certificate issuer and by redirect.pizza support

Current situation

HTTPS works correctly in Chrome, Edge, Safari, and on mobile browsers HTTPS works correctly on the same computer when using Chrome In Firefox (both normal and Private windows) I continue to receive “Secure Connection Failed / Not Secure”

What I have already tried

Cleared cookies and site data for the domain Cleared all recent history (including cache) Tested in a Private Window Restarted Firefox multiple times

None of these steps resolved the issue in my current Firefox profile. It appears Firefox has cached the previous (invalid) certificate state and is not refreshing it, even though a valid certificate is now being presented by the server. Could you please advise:

Is there a more thorough way to force Firefox to discard a cached SSL certificate for a specific domain? Or is this a known issue that requires a fix on the Firefox side?

I am happy to provide any additional technical details or screenshots if needed. Thank you for your help. Best regards, Jamie Lloyd