Firefox Community Forum

To be honest. Firefox is starting to be a big pain to use. I'm starting to see more and more of this screen where it say's "Be careful. Something doesn't look right" Even when i go to the advance and say proceed. Nothing happens and i'm getting no where. I know many of the sites don't have anything to do with asking for credit card, Scam or even having popup's. I test the sites in other browsers and there work without any issues. But Firefox is starting to lock me out of many sites due to this. How can i make this stop. As i used Firefox for many years.

The sample that is in the screenshot is a Anime data base that i have also used for years. But today shows this. But was working fine yesteday. What is going on and how can i fix it. So i can start using the browser that i love on the sites i want to.

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)

Have used Firefox for years. Today, went to standard sites (eg weather info, local blog site) and get told they aren't secure and can't be loaded. Have tried re-installing Firefox, clearing cookies but no change. No problem with same sites from Chrome. Message is:

Looks like there’s a problem with this site

www.portlandbirdobs.com sent back an empty page. What can you do about it?

   The site could be temporarily unavailable or too busy. Try again in a few moments.
   If you are unable to load any pages, check your computer’s network connection.
   If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the web.

Error Code: NS_ERROR_NET_EMPTY_RESPONS

I have never ever had a problem getting into my bank account until this evening.

Says it is insecure.

How can this happen? I really need to get into my account!

Did Not Connect: Potential Security Issue

Firefox detected a potential security threat and did not continue to nrega.nic.in because this website requires a secure connection.

What can you do about it?

nrega.nic.in 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.

Probably nothing, since it’s likely there’s a problem with the site itself.

Hello, I run a movie and drama-related website: https://tvmon.com.co/. Recently, I’ve noticed that Firefox occasionally throws the following error when trying to access the site:

"Secure Connection Failed An error occurred during a connection to tvmon.com.co. . The OCSP response contains an invalid signing certificate. Error code: SEC_ERROR_OCSP_INVALID_SIGNING_CERT"

This issue is very strange because:

1. The site loads fine in Chrome, Edge, and Safari.

1. My SSL/TLS certificate is valid, up-to-date, and passes external tests (SSL Labs, etc.).

1. The error only appears occasionally in Firefox, refreshing sometimes fixes it, sometimes not.

1. Hosting and server logs show no issues at all.

I suspect this is related to Firefox’s stricter OCSP validation, but I’m not sure how to debug or resolve it. Since my site streams drama and movie content, this error is frustrating for users who rely on Firefox.

Has anyone else experienced this intermittent OCSP signing certificate error? Is there a known fix or workaround for Firefox-specific validation issues?

Secure Connection Failed

An error occurred during a connection to nrega.nic.in. Peer’s Certificate has been revoked.

Error code: SEC_ERROR_REVOKED_CERTIFICATE

   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.

Clear Error code: PR_END_OF_FILE_ERROR This is only on Amazon.com. Secure Connection Failed

An error occurred during a connection to www.amazon.com. PR_END_OF_FILE_ERROR

Error code: PR_END_OF_FILE_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 trying to access many popular websites with Firefox on my Fedora 43 installation, I am greeted with a security warning page with the SEC_ERROR_UNKNOWN_ISSUER error. For most of these websites I can simply accept and continue, but HSTS-only sites will not permit this.

Affected websites include but are not limited to (based on exceptions in the certificates section of Firefox settings):

• github.io (many subdomains)
• purdue.edu (many subdomains)
• iu.edu
• ebay.com
• cbsnews.com
• iwm.org.uk
• home.cern
• celestrak.org

Any help in resolving this is appreciated.

Hi Love Firefox and use it every day to manage clients Google Ads accounts. Updated to latest version and now I'm getting this warning when I'm trying to access ads.google.com Doesn't appear that I can add an exception, is there a work around that I can use. Look forward to hearing back. Thanks in advance

Paul

Site: https://www.thegamer.com Firefox refuses to load the site, it does not even show the certificate when clicking on the lock. Using the certificate manager, add exception does not work too, it just refuses to store the certificate. But at least THERE I can VIEW the certificate, which proves it is valid and FIREFOX is at fault:

https://www.ssllabs.com/ssltest/analyze.html?d=www.thegamer.com&latest shows "IO exception" when trying to check the CRL, but gives an A+. Yet Firefox does not even give me the "Continue anyway" possibility. This it tiering, I hate using google chrome based browsers, but of course, it works there. Server 2025, only MS-defender at its default settings.

Subject Name Common Name thegamer.com Issuer Name Country US Organization Let's Encrypt Common Name E8 Validity Not Before Mon, 13 Oct 2025 23:03:42 GMT Not After Sun, 11 Jan 2026 23:03:41 GMT Subject Alt Names DNS Name

• .thegamer.com

DNS Name thegamer.com Public Key Info Algorithm Elliptic Curve Key Size 256 Public Value 04:0E:95:16:C4:A2:23:9D:81:AD:D7:70:4C:4B:A5:F7:68:0E:33:E2:A0:1C:81:6D:0F:1C:F5:C8:EF:5B:C8:64:AD:15:86:5D:5E:E6:FA:A6:DB:41:86:A5:F0:28:7A:45:F4:8D:75:B3:18:43:E9:0F:7C:75:10:AE:F8:A0:04:7B:D5 Miscellaneous Serial Number 06:6C:A7:00:7C:ED:C0:50:E2:FD:4F:6C:A0:8C:0F:86:2B:AD Signature Algorithm ECDSA with SHA-384 Version 3 Download PEM (cert)PEM (chain) Fingerprints SHA-256 D0:D5:E8:73:9E:6D:B1:2D:EC:5D:47:0D:70:BF:58:1C:AC:A5:D3:89:20:6D:54:15:09:E8:42:9C:82:F7:4F:8F SHA-1 53:E6:54:B5:37:0F:4B:23:BE:73:8A:6B:37:6B:BE:A6:A5:86:E4:5B [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Basic Constraints Certificate Authority No [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Key Usages Purposes Digital Signature Extended Key Usages Purposes Server Authentication, Client Authentication Subject Key ID Key ID 53:6A:02:33:30:1C:AD:4D:3B:F2:9F:4D:6D:E4:33:26:31:69:8F:61 Authority Key ID Key ID 8F:0D:13:A2:F6:2E:7E:D1:50:6C:33:18:38:5D:59:8E:23:72:91:CA CRL Endpoints Distribution Point http://e8.c.lencr.org/46.crl Authority Info (AIA) Location http://e8.i.lencr.org/ Method CA Issuers Certificate Policies Policy Certificate Type ( 2.23.140.1.2.1 ) Value Domain Validation Embedded SCTs Log ID 0E:57:94:BC:F3:AE:A9:3E:33:1B:2C:99:07:B3:F7:90:DF:9B:C2:3D:71:32:25:DD:21:A9:25:AC:61:C5:4E:21 Signature Algorithm SHA-256 ECDSA Version 1 Timestamp Tue, 14 Oct 2025 00:02:12 GMT Log ID 19:86:D4:C7:28:AA:6F:FE:BA:03:6F:78:2A:4D:01:91:AA:CE:2D:72:31:0F:AE:CE:5D:70:41:2D:25:4C:C7:D4 Signature Algorithm SHA-256 ECDSA Version 1 Timestamp Tue, 14 Oct 2025 00:02:12 GMT

Subject Name Country US Organization Let's Encrypt Common Name E8 Issuer Name Country US Organization Internet Security Research Group Common Name ISRG Root X1 Validity Not Before Wed, 13 Mar 2024 00:00:00 GMT Not After Fri, 12 Mar 2027 23:59:59 GMT Public Key Info Algorithm Elliptic Curve Key Size 384 Public Value 04:D1:65:F2:5E:DC:4B:B4:0C:02:9C:D2:B2:FA:EE:E9:6C:AB:3A:AE:38:A1:F4:D4:39:32:33:C5:42:D4:CC:33:0C:34:C7:21:20:90:70:5C:E8:62:2F:1C:71:B3:42:D7:79:BE:46:0D:C1:DB:47:A1:13:A0:C7:DF:81:26:63:3B:D4:8D:1D:F6:3D:82:33:32:F6:F4:2B:E7:F5:96:3A:B4:13:67:18:7B:6B:3E:8D:48:D9:EA:DE:ED:AE:6D:3E:87:4C Miscellaneous Serial Number 63:95:93:63:C2:4E:70:82:71:59:18:BF:C3:D7:ED:56 Signature Algorithm SHA-256 with RSA Encryption Version 3 Download PEM (cert)PEM (chain) Fingerprints SHA-256 83:62:4F:D3:38:C8:D9:B0:23:C1:8A:67:CB:7A:9C:05:19:DA:43:D1:17:75:B4:C6:CB:DA:D4:5C:3D:99:7C:52 SHA-1 54:31:7E:B0:76:5F:0B:C6:74:85:51:84:EB:83:74:B4:19:9E:46:55 [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Basic Constraints Certificate Authority Yes [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Key Usages Purposes Digital Signature, Certificate Signing, CRL Signing Extended Key Usages Purposes Client Authentication, Server Authentication Subject Key ID Key ID 8F:0D:13:A2:F6:2E:7E:D1:50:6C:33:18:38:5D:59:8E:23:72:91:CA Authority Key ID Key ID 79:B4:59:E6:7B:B6:E5:E4:01:73:80:08:88:C8:1A:58:F6:E9:9B:6E CRL Endpoints Distribution Point http://x1.c.lencr.org/ Authority Info (AIA) Location http://x1.i.lencr.org/ Method CA Issuers Certificate Policies Policy Certificate Type ( 2.23.140.1.2.1 ) Value Domain Validation

Subject Name Country US Organization Internet Security Research Group Common Name ISRG Root X1 Issuer Name Country US Organization Internet Security Research Group Common Name ISRG Root X1 Validity Not Before Thu, 04 Jun 2015 11:04:38 GMT Not After Mon, 04 Jun 2035 11:04:38 GMT Public Key Info Algorithm RSA Key Size 4096 Exponent 65537 Modulus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iscellaneous Serial Number 00:82:10:CF:B0:D2:40:E3:59:44:63:E0:BB:63:82:8B:00 Signature Algorithm SHA-256 with RSA Encryption Version 3 Download PEM (cert)PEM (chain) Fingerprints SHA-256 96:BC:EC:06:26:49:76:F3:74:60:77:9A:CF:28:C5:A7:CF:E8:A3:C0:AA:E1:1A:8F:FC:EE:05:C0:BD:DF:08:C6 SHA-1 CA:BD:2A:79:A1:07:6A:31:F2:1D:25:36:35:CB:03:9D:43:29:A5:E8 [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Basic Constraints Certificate Authority Yes [This extension has been marked as critical, meaning that clients must reject the certificate if they do not understand it.] Key Usages Purposes Certificate Signing, CRL Signing Subject Key ID Key ID 79:B4:59:E6:7B:B6:E5:E4:01:73:80:08:88:C8:1A:58:F6:E9:9B:6E

I am writing to report a recurring technical issue that began appearing today across multiple devices.

When attempting to access Google websites (specifically Gmail and Google News) using the Firefox browser, users are being prompted to identify themselves via a security certificate. Previously, this authentication step did not occur, and access was seamless.

Key Observations:

Impact: We have confirmed this behavior on three firm-issued computers as well as one personal device.

Browser: The issue is isolated to Firefox; other browsers appear unaffected.

Timing: This behavior was not present yesterday; it started manifesting today.

We suspect this may be related to a recent network configuration change, a new security policy rollout, or a browser update that has altered how Firefox handles trusted connections to Google services.

Could you please inform me whether there have been any recent changes to our SSL inspection proxies, root certificate stores, or DNS configurations? Additionally, does anyone else on the team have visibility into a widespread incident affecting Google certificates, or should we proceed with troubleshooting individual profiles?

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.

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…

Untill last night i could conect with that site https://imtw.ru and its sub forums without eny problem . Today when i press the link i recieve a message that the connection is rejected "Failure to secure connection". As you van see it has the https:// infront and i repeat i was able to connect last night. What may be wrong?

The SSL cert has been installed by the entity (Gridhost) from whom I have bought it for 20 years. And as explained, Firefox still shows it as Not Secure while Chrome say it is secure.

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.