Firefox Community Forum

I am able to open all these sites in Edge and Chrome. Firefox is not allowing me to open any website including https://support.mozilla.org/1/firefox/141.0.3/WINNT/en-US/firefox-help

Here is one for www.theepochtimes.com Firefox blocked your visit to this site because the signature on the certificate provided for linkprotect.cudasvc.com isn’t valid.

Error code: SEC_ERROR_BAD_SIGNATURE

View Certificate

https://linkprotect.cudasvc.com/url?a=https%3a%2f%2flists.theepochtimes.com%2flinks%2fdYekYfa9b%2fHhryKHE6n%2fm46Mv1lM35xm%2ffPxqlcxbEy&c=E,1,ZCIg6L-Y-rIKvrOC91Rng41YHEp3yXHnFOrkZ-dEbsu8eJmVYw5eygLlFsHlgdf1Tmry7UZgvuCl6QoNJHES1kUyjNFgc3z8J5-hU70LqRt8blmn&typo=1

Peer’s certificate has an invalid signature.

HTTP Strict Transport Security: false HTTP Public Key Pinning: false

Certificate chain:

MIIB3TCCAYKgAwIBAgIIOvW4RpHf51AwCgYIKoZIzj0EAwIwTTELMAkGA1UEBhMC TFQxFTATBgNVBAoMDE5vcmRWUE4gUy5BLjEnMCUGA1UEAwweTm9yZFZQTiBTLkEu IC1UaHJlYXRQcm90ZWN0aW9uMB4XDTI1MDgyNTE5MTA1NFoXDTI2MDgyNTE5MTU1 NFowJDEiMCAGA1UEAwwZKi5saW5rcHJvdGVjdC5jdWRhc3ZjLmNvbTBZMBMGByqG SM49AgEGCCqGSM49AwEHA0IABGrx92NDDePfCVmGrn4StYMr6XU2mdhqpiE51CmT XEnX6cYCaE1KyVrw09JFubcGZSmUUllYqKjKop6A4uds/5SjdTBzMB0GA1UdDgQW BBTUcdvR66YYJKl/X5qqiMfeJn5XtjATBgNVHSUEDDAKBggrBgEFBQcDATA9BgNV HREENjA0ghkqLmxpbmtwcm90ZWN0LmN1ZGFzdmMuY29tghdsaW5rcHJvdGVjdC5j dWRhc3ZjLmNvbTAKBggqhkjOPQQDAgNJADBGAiEA2a31LBw2Ab2UixVdpVQpJwx0 hW5mLG/KCvuyrACqUQ8CIQDAnirOaJT0OuV3d4jeznV7DaLdY7RqVDXyuGNZwXDZ Fw==

Secure Connection Failed

The connection to www.tab.com.au was interrupted while the page was loading.

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

Subject: Urgent Assistance Needed with Certificate Installation

Dear Team,

I hope this message finds you well. I am in urgent need of assistance regarding a Linux-based system where we have the Firefox browser installed. I need to establish a secure connection with one of my servers, which requires the installation of a certificate.

However, I am unable to locate the certificate export button in the certificate view or anywhere else in the browser. I have tried several methods without success.

Could you please help me with this issue as soon as possible? Your guidance would be greatly appreciated.

Thank you very much!

Best regards, Kishor

Loading website for BacaPoa.frontsteps.com does not work, now fails ("not secured") . This is business site I have for years.? [windows 11] Is the a bypass or override I can do? JR

i can't do a search. I keep getting "problem loading page" and "secured connection failed" This is happening on both my windows 7 computer and my windows 10 computer. The same thing is happening if I try a google search as well.

An error occurred during a connection to in.pinterest.com. PR_CONNECT_RESET_ERROR

Error code: PR_CONNECT_RESET_ERROR

   The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
   Please contact the web site owners to inform them of this problem.

An error occurred during a connection to ezproxy.yu.edu.jo. PR_CONNECT_RESET_ERROR

Error code: PR_CONNECT_RESET_ERROR

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

Learn more…

Secure Connection Failed

An error occurred during a connection to citizen.jhpolice.gov.in. PR_CONNECT_RESET_ERROR

Error code: PR_CONNECT_RESET_ERROR

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

Learn more…

When I bring up the certificate-expired URL

<https://oaklandwiki.org/>

in Firefox 149.0 on Windows 11 I am told "You have added a security exception for this site." But not how to remove it. How do I do that? I did not see anything in Settings or about:config; did I miss it?

Hello,

The website I log in for internet banking (https://www.sparkasse-rhein-maas.de/de/home.html) is shown as written in brackets when opened in Edge, but as www.sparkasse-rhein-maas.de/de/home.html when I open it in firefor. And Firefox tells me it's not safe when I want to log in. BUT - as I've only just discovered when I copied and pasted it in here - when copied it shows as https://www.sparkasse-rhein-maas.de/de/home.html, so safe after all? How can that be? I hope there's a good explanation.

Thanks in advance Bettina

Moderator note: This question has been edited to correct the formatting.

Hello,

Since this morning, I haven't been able to access Bsky on my laptop because of a supposed HSTS risk, which means I can't add an exception to visit it. I use Firefox on my Android and going to the mobile version of the website lets me in no problem, so I assume there's an issue with my laptop.

I'd usually wait a few days and let it solve itself but just in case it's something on my end, I'd like to solve it! I'm on 151.0.4 (64-bit), don't use a VPN or an anti-virus, I have a couple of privacy add-ons but they've been here forever and they've never caused a fuss. I can post a screenshot of the error code and the certificate it sends me if it's any help.

I'd appreciate any pointers! Thanks!

I just installed Firefox on my PC haven't had it on this computer since reinstalling windows - I imported my bookmarks and passwords from Edge, thinking it would be a seamless transition, since I used Firefox in the past without much trouble.

Two weeks on, about 95% of every page I open gives an error similar to the one below, and I have to shift+refresh several times to get it to reload before it goes away, (some sites still don't open).

I wonder how common this issue is, and how people fixed it?

Be careful. Something doesn't look right.

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

Go back (Recommended)

Hide advanced

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 connect.mozilla.org. The certificate is only valid for: *. eero.com. 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 Jun 5, 2026 10:58:34 AM GMT+10

Proceed to connect.mozilla.org (Risky)

Hello, I am facing a very strange and frustrating issue with my website https://biografieblick.de/, and it is only happening on the firefox browser other browsers like chrome, edge or safari are loading the site perfectly fine. The Issue is it occurs occasionally, Yeahh IDK why. When I try to visit my site, Firefox gets stuck on a screen that says "Checking if the site connection is secure" and it looks like an loop sometimes.

This looks exactly like a cloudflare turnstile loop but I am NOT using cloudflare. I have double checked my DNS records and explicitly confirmed this with my web hosting provider. This block only triggers when using firefox.