Firefox Community Forum

Beginning today, I suddenly cannot access numerous websites when I use Mozilla Firefox 151.0.2. Examples include Amazon, and Google, et al. Attempts to do so consistently fail at the point of performing a TLS handshake, when I am advised that "secure connection failed". Kindly refer to the attached screenshots. I have no difficulty whatsoever accessing the same websites when I use other browsers, such as Google Chrome and MS Edge. I previously had Mozilla Firefox enabled as my default browser, but I have had to change this, given these "challenges". Please advise how I can fix this. Best regards and many thanks.

Using firefox 140.6.0esr on Windows 10 with noScript and uBlock Origin

Infrastructure for my health insurance provider website uses a self-signed certificate. The infra has a different URL from the main page and was initially failing with "CORS failed", which turned out to be the cert issue.

I copied the infra URL from the dev tools network log and opened it directly, and accepted the invalid cert. I can see the new exception in cert_override.txt.

Then, after unblocking the site in uBlock origin, POST and GET requests to the infra URL succeed, but OPTIONS requests are still failing with "CORS failed", and security status "SEC_ERROR_UNKNOWN_ISSUER"

Is there anything else I can do so the OPTIONS request honors the exception in cert_override.txt?

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.

Why does my older computer running Windows 7 keep losing the ability to access "https:// sites"?

To resolve, I have to reset the network adapter (sometimes successful) or restart the computer to access these sites.

So I'm trying to access Greenfly but I'm getting this error message: SEC_ERROR_REVOKED_CERTIFICATE.

Please see attached image as all checks are good for the credentials. I've tried erasing cookies but no luck.

Any other options?

Firefox Nightly | 138.0a1 (2025-03-10) (aarch64) MacBook Pro | M2 2022 | Sequoia 15.3.1

Be careful. Something doesn’t look right.

Firefox spotted a potentially serious security issue with www.aol.fr. Someone pretending to be the site could try to steal things like credit card info, passwords, or emails. ??????? I used Aol since 1998 !!!!!!!!

need to be able to download my old sites. and stop getting error 522 can not connect to some sites due to not secure anymore... help need to watch some movie sites.. Jose

I am trying to log on to Gordon Bernard Calendar Co once there I am informed that it is an insecure web site. I have been there many times. The GB web person says the prob. is on my end. My computer is old and I have always used version 7.

Joe

Your computer thinks it is May 1, 2026, which prevents Firefox from connecting securely. To visit www.olx.com.br, update your computer clock in your system settings to the current date, time, and time zone, and then refresh www.olx.com.br.

When I enter a company name into search this message appears:

Secure Connection Failed

An error occurred during a connection to vanilla-search.com. SSL received a record that exceeded the maximum permissible length.

Error code: SSL_ERROR_RX_RECORD_TOO_LONG

   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…

I have been having problems getting access to sites. I keep getting 502 Bad Gateway Certificate verify failed: unable to get local issuer certificate. What can I do? For example, I have been trying to access EFTPS to schedule payments or IRS and get same message. What should I do?

On some of my accounts that I use every day I keep getting unsecured site and can't advance to my site. Michales is one of them so I can't use my coupons to buy my products.