I don't think there is a bypass for that particular error code -- SSL_ERROR_NO_CYPHER_OVERLAP -- because Firefox and the server need to agree on the encryption cipher in order to form a connection.

Is this a public website? You could share the URL with us, or test it using the following page and see whether their Firefox test machines can connect:

https://www.ssllabs.com/ssltest/

If these are internal servers in your company, does your IT have any explanation for the problem?

Tried testing them on the link but it indicates that IP addresses are not allowed.

These are the links I´m trying to access: https://74.201.159.110/EZrate/index.php https://74.201.159.25/gcszzdasaro/index.php

I guess you must have already made an exception for the other problems before you got the cipher error:

74.201.159.110 uses an invalid security certificate.
The certificate is not trusted because it is self-signed.
The certificate is only valid for .
The certificate expired on Wednesday, July 10, 2013, 3:55:43 PM. The current time is November 13, 2018, 2:25 PM.
Error code: MOZILLA_PKIX_ERROR_SELF_SIGNED_CERT

I don't think I'm going to make an exception to see what happens next, sorry.

Do your other browsers work with the site?

No, having the same issue over Chrome & Edge. But, this only happens from my laptop. Able to access from ipad / iphone.

Even worse, only I started having these issues. Other users working remotely are able to access with no issue.

Since all browsers are affected, could it be a "man in the middle" such as your security software? They make two secure connections, one with Firefox and one with the site, so they can read your browsing. This article describes some of the common ones and how to disable them from filtering secure connections in Firefox: How to troubleshoot security error codes on secure websites.

Indeed it was Bitdefender Security Software. Already had Exceptions configured for both IPs but for some reason, on last update from the software, they stopped being considered; although are still detailed as such. Turned off Scan SSL, which is now named Encrypted Web Scan, and all is finally back to normal!

Thank you for the help!!!

I have this problem, also. This is the website I want to access: https://mychart.sclhealth.org/MyChart/ It works in Explorer. I tried to add it as an exception to no avail.

Hi McMom, that address doesn't work for me, either.

In case they changed it, could you go through the link on the upper right of the home page and see whether you end up in the same place or somewhere new?

https://www.sclhealth.org/

If the problem continues, please contact them for assistance. I don't suggest messing with the security of your connection to sites that handle sensitive information.

See next post

Hi McMom, I ran the address through a tester and none of their Firefoxes can connect either:

https://www.ssllabs.com/ssltest/analyze.html?d=mychart.sclhealth.org

It seems to be an issue with the site's cipher suites not being compatible with Firefox. So you'll need to use a different browser for the time being. If you prefer Firefox, please point them to that page and ask them to make the site compatible.

Thank you SO MUCH, jscher2000!

If I run the test at this time then the result indicates that the mychart.sclhealth.org site works and I currently have no problems.

TLS 1.2 and TLS_RSA_WITH_AES_256_CBC_SHA

Interesting. Thanks!