SSL_ERROR_NO_CYPHER_OVERLAP Your server apparently doesn't offer any cipher suites necessary to establish a secure https connection that are supported in Firefox. You can check what kind of cipher suites Firefox can make use of by visiting; https://www.ssllabs.com/ssltest/viewMyClient.html

Firefox will just show the SSL_ERROR_NO_CYPHER_OVERLAP error when encountered any site using the RC4 cipher.

Citibank Fx is the largest institutional forex market maker (primary dealer) in the world, and its site cannot be accessed through Firefox, though every other browser I've tried can.

This is a problem.

Hi CharlesStanford, when I try the URL I get the same error:

https://www.citifx.com/

We often suggest using an SSL Labs test page to examine server configurations to see whether that identifies any issues. When I submit the problem address, all of their test installations of Firefox show

Server sent fatal alert: handshake_failure

The server only supports three "weak" ciphers and Firefox does not match up with any of those.

Test results page: https://www.ssllabs.com/ssltest/analyze.html?d=www.citifx.com

Your current browser protocols and ciphers: https://www.ssllabs.com/ssltest/viewMyClient.html

I'm not aware of any way to add more ciphers to Firefox. For now you'll need to use a different browser with the site.

Could you also contact their support and point them to the above pages and suggest that they update their cipher list so customers can use Firefox with the site?