This webpage is not available ERR_SSL_VERSION_OR_CIPHER_MISMATCH

This webpage is not available

ERR_SSL_VERSION_OR_CIPHER_MISMATCH

A secure connection cannot be established because this site uses an unsupported protocol or cipher suite. This is likely to be caused when the server needs RC4, which is no longer considered secure. As of 2016 all major browsers including Google, Microsoft and Mozilla will no longer support RC4. RC4 is a stream cipher designed in 1987 that has been widely supported across browsers and online services for the purposes of encryption. Multiple vulnerabilities have been discovered in RC4 over the years, making it possible to crack within days or even hours.

To temporarily enable it in the FireFox browser use the following:


Type: "about:config", in the URL entry text box. 

You may see the warning..."This might void your warranty"....Click on "I'll be careful, I promise" 


Next, it will display the internal hidden configs.


Scroll down and lookup for "security.ssl3.rsa_rc4_40_md5" and double click on the line to change the Value from "false" to "true"

This will enable the support for SSL3-EXP-RC4-MD5 cipher.

Other export ciphers that can be enabled are:

security.ssl3.rsa_1024_des_cbc_sha
security.ssl3.rsa_1024_rc4_56_sha

This will enable the following ciphers corresponding to cipher suite list on NS VPX
TLS1-EXP1024-RC4-SHA
TLS1-EXP1024-DES-CBC-SHA

You should now be able to access the service to update the ciphers. Once updated switch your browser settings back to previous settings.


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