> I am quite new in both Linux and MIDAS.
> I have install MIDAS on my desktop by going through this link: 
> https://midas.triumf.ca/MidasWiki/index.php/Quickstart_Linux 
> 
> in the last step when I send "mhttpd" command and try to open the link 
> https://localhost:8443 (of course, changing the localhost with my host name), it 
> failed to connect and shows this error: SSL_ERROR_NO_CYPHER_OVERLAP (please see 
> attached file includes a screenshot of the error).

What Linux? (on most linuxes, run "lsb_release -a")
What version of midas? (run odbedit "ver" command)
What version of firefox? (from the "about firefox" menu)

> I have tried many ways to solve this problem: In Firefox: going to option/privacy 
> and security/ security and uncheck the option "Block dangerous and deceptive 
> content". but it does not help.

No you cannot fix it from inside firefox. The issue is that the overlap of encryption methods
supported by your firefox and by your openssl library (used by mhttpd) is an empty set.
No common language, so to say, communication is impossible.

So either you have a very old openssl but very new firefox, or a very new openssl but very old 
firefox. Both very old or both very new can talk to each other, difficulties start with greater  
difference in age, as new (better) encryption methods are added and old (no-longer-secure) 
methods are banished.

BTW, for good security we recommend using apache httpd as the https proxy (instead of built-in 
https support in mhttpd). (I am not sure what it says in the current documentation). (But apache 
httpd will use the same openssl library, so this may not solve your problem. Let's see what 
versions of software you are using, per questions above, first).

K.O.