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Thunderbird and cipher to use.

Offline mmccarn

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Thunderbird and cipher to use.
« on: October 22, 2015, 01:10:06 PM »
A thunderbird update that installed itself on my systems between 10/6 and 10/7 started failing the process of negotiating the cipher to use.

I found the problem by looking at the 'Error Console' in Thunderbird (Tools -> Error Console).  Other than the error in the error console there was no indication of any problem - Thunderbird would say 'connected to...' my server in the lower left corner, but no mail would come in.

I had customized the 'CipherSuite' on my server in order to get the highest possible score on the Qualys SSL Server Test.  I had to relax the settings in order to get Thunderbird to work again (I had RC4 disabled, after I re-enabled it Thunderbird started working again).

I was making my changes using 'config setprop modSSL CipherSuite ....', but I think I could have set a different ciphersuite for qpsmtpd without changing the webserver settings using 'config setprop qpsmtpd tlsCipher ...'