418 For years, I've been using a website that's crucial to my professional work. It's a national archive website. Today, I suddenly got an error about a missing certificate for this website, and there's no way to bypass it. The cause isn't the archives, but the latest Firefox update. Please fix this immediately or refund me for the days I'm off work—or maybe I'll lose my job because of you.

I can't open netflix or https://predatorhunteroutdoors.com . Why am I getting this message?

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.

Just updated Firefox desktop (Win 10 with ESU) to 140.10.0ESR and now every site I try to access gives

Secure Connection Failed An error occurred during a connection to www.google.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 website owners to inform them of this problem.

Sites were all working fine literally right before. No other changes at all. Have restarted a few times. Have disabled antivirus and adblocker extensions. Same problem including at google.com and even firefox. Note on the About Mozilla Firefox window says " Failed to check for updates". Also cannot even use the links there to go to What's new or Firefox help etc. (Gives Secure Connection Failed error). No proxy server. Have tried turning anti virus completely off. Just a combined modem/router -- basically vanilla.

Firefox is my primary browser so this is extremely disruptive. I am using Edge to access sites and post this.. though curiously enough I noticed it gave some error when checking for updates. Do not want to do anything there or will lose complete access.

Any suggestions .. or how to go back to a previous version, if necessary. Need a workable connection to file taxes next week so this is important. Thank you.

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

Hello, I'm French and I'm not very good at English I’ve been a Mozilla user for many years and am very satisfied with it. I’m having trouble interacting with the Ohm Energie website. I wanted to sign up for an electricity plan. The Ohm Energie page opened fine in my browser, but as soon as I tried to interact with it—for example, to request a quote—I received the following security notification: “Firefox has detected a potentially serious security issue with espace-client.ohm-energie.com. Someone impersonating the site might try to steal things like credit card information, passwords, or email addresses.” I was forced to use Chrome to sign up for my plan. I’m not the only Firefox user facing this issue. I called Ohm Energie and was told that many other customers have also encountered this problem. I’d like to be able to access my Ohm Energie account via Firefox—what can I do? I should mention that I’m not very experienced in resolving this type of issue. Thank you for your help

I am unable to sign in due to Firefox reporting ISP FFL website security certificate being revoked. I do not remember my password to try another browser. Please help

I am filing my taxes through Intuit. Something I have done for years with NO problem. I realize my system is old and something about the security certificate somewhere is not correct and cannot be changed. I am NOT a technician and all this security stuff is way above me. Normally a box pops up saying Advanced settings and another box that allows me to Trust the site and I am logged in. Now I want Intuit to download my CRA information and it cannot because of this certificate thing and there is no bypass. So now you want me to contact the web owner, whoever that is, the Government of Canada??? Good luck. and have a technical discussion that requires at least three degrees from MIT, which I do not have, to solve the issue???? This is bloody nuts and now I cannot file my taxes. I am about to go totally insane. This is way beyond the average individual's skill set.

Does anyone know how I can get around this??

Firefox browser has stopped opening websites on my Dell laptop. Get "secure connection failed" error message. Other browsers work just fine. I have refreshed, uninstalled and reinstalled Firefox from both firefox website (using Brave browser) and from MSN store.

I have a local Rocky Linux server running a nginx web server. I am using a Macos laptop. I am trying to install a self signed ssl certificate using openssl on my web server.. The certificate I generated works with Safari but not with Firefox. I have copied the certificate to both Safari and Firefox for local use. Privacy and Security, Manage Certificates, Your Certificates. Firefox complains that that my TLS is tls 1.1, when I am using tls 1.3:

An error occured during connection to tls-v1-1.badssl.com:1011. Peer using unsupported version of security protocol.

My test on my server shows:

sudo curl -v https://caprock.home

Connected to caprock.home (192.168.2.44) port 443 (#0)

• ALPN, offering h2
• ALPN, offering http/1.1
• CAfile: /etc/pki/tls/certs/ca-bundle.crt
• TLSv1.0 (OUT), TLS header, Certificate Status (22):
• TLSv1.3 (OUT), TLS handshake, Client hello (1):
• TLSv1.2 (IN), TLS header, Certificate Status (22):
• TLSv1.3 (IN), TLS handshake, Server hello (2):
• TLSv1.2 (IN), TLS header, Finished (20):
• TLSv1.3 (IN), TLS change cipher, Change cipher spec (1):
• TLSv1.2 (IN), TLS header, Unknown (23):
• TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
• TLSv1.2 (IN), TLS header, Unknown (23):
• TLSv1.3 (IN), TLS handshake, Certificate (11):
• TLSv1.2 (IN), TLS header, Unknown (23):
• TLSv1.3 (IN), TLS handshake, CERT verify (15):
• TLSv1.2 (IN), TLS header, Unknown (23):
• TLSv1.3 (IN), TLS handshake, Finished (20):
• TLSv1.2 (OUT), TLS header, Finished (20):
• TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
• TLSv1.2 (OUT), TLS header, Unknown (23):
• TLSv1.3 (OUT), TLS handshake, Finished (20):
• SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
• ALPN, server accepted to use http/1.1
• Server certificate:
• subject: C=US; ST=Colorado; O=Caprock Development; OU=Caprock Development Home Base; CN=caprock.home; emailAddress=mike@white-home.com
• start date: Aug 12 19:26:04 2025 GMT
• expire date: Nov 13 19:26:04 2032 GMT
• common name: caprock.home (matched)
• issuer: C=US; ST=Colorado; L=Canon City; O=Caprock Development; OU=Caprock Development Home Base; CN=caprock.home; emailAddress=mike@white-home.com
• SSL certificate verify ok.
• TLSv1.2 (OUT), TLS header, Unknown (23):

> GET / HTTP/1.1 > Host: caprock.home > User-Agent: curl/7.76.1 > Accept: */* >

• TLSv1.2 (IN), TLS header, Unknown (23):
• TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
• TLSv1.2 (IN), TLS header, Unknown (23):
• TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
• old SSL session ID is stale, removing
• TLSv1.2 (IN), TLS header, Unknown (23):
• Mark bundle as not supporting multiuse

< HTTP/1.1 200 OK < Server: nginx/1.20.1 < Date: Tue, 28 Apr 2026 13:17:26 GMT < Content-Type: text/html; charset=UTF-8 < Transfer-Encoding: chunked < Connection: keep-alive < X-Powered-By: PHP/8.3.30 <

Caprock.home

• Connection #0 to host caprock.home left intact

Furthermore I can't seem to delete the certificate from Firefox and re add it?

I just got a Netgear router. Firefox won't let me connect because of the self-certification. I can only get on the internet via my Proton VPN. How can I fix this?

Specifically, I get this message--The certificate is not trusted because it is self-signed.

Illustration of a fox looking at an orange warning sign. Be careful. Something doesn’t look right.

Firefox spotted a potentially serious security issue with hrms.devrising.in. 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 hrms.devrising.in. The certificate is only valid for: isp.afd2.jiohs.net, signup.jiohs.net, frontend.afd2.jiohs.net, www.frontend.afd2.jiohs.net, acc.afd2.jiohs.net, blk.jiohs.net.

Ever since I updated Firefox, my website has stopped loading properly. It works fine in Chrome and Edge, but in Firefox, I get a security warning page instead.

The message says:

Your connection is not secure

The website tried to negotiate an inadequate level of security. https://reminniapk.com/

uses security settings that might be outdated or not supported by Firefox, so the browser blocks it.

Error code: NS_ERROR_NET_INADEQUATE_SECURITY

I haven’t made any major changes recently, so I’m not sure why this started happening. Is this something that needs to be fixed on the server side, or is there any setting in Firefox that could be causing this?

Any help would be appreciated.

error code SEC Error expired certificate

This started on 3/18 evening

I cannot play games plus will now lose my 7M for each daily login and the four spins I can do every four hours

Hi Had some problems with the computer. According to Microsoft the dll error was caused by the new Adobe acrobat. Trying to fix this problem some of the websites in Firefox are having now problems. EXP. Kohl's Error code: SEC_ERROR_REVOKED_CERTIFICATE. Home Depot Oops!! Something went wrong. Please refresh page. This is only happening in Firefox with Windows 7, Firefox version 115.33.Oesr 64 bit. When I access these two websites on Chrome in the same computer everything is fine.

What is causing these errors in Firefox????? Can you please help!!!!!

Amy

keep getting message [ sometjing dosen't look right ] and certificate revoked for my bank login it lets me go to the website but wont let me log into it. this is for blue federal credit union bank so i have to use a different browser for it, it works fine on other browser like edge .but not Firefox please help with this issue i like Firefox would hate to have to switch browsers but if this doesn't get resolved then ill have no choice too thank you

I can't open my Wordpress website. I am using BlueHost portal. I get a message that says Something looks wrong and the following error code. SSL_ERROR_NO_CYPHER_OVERLAP

Whenever i try to connect to any site, it fails to load and displays the following error message:

This web site requires a secure connection. - The page you are trying to view cannot be shown because this web site requires a secure connection. - The issue is most likely with the web site, and there is nothing you can do to resolve it. - You can notify the web site’s administrator about the problem.

When i press 'advanced' it says: [Site name] 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.

This happens on every site i try to visit. I am on a samsung phone running android version 15. Other browsers do not have this problem (i am sending this from opera), and firefox works fine on my other devices.