Hi, I upgraded my Stunnel server machine to CentOS 6.8 and post upgrade , the stunnel too got upgraded to stunnel 4.29 on x86_64-redhat-linux-gnu with OpenSSL 1.0.1e-fips 11 Feb 2013 . Now since then many of the stunnel client using newer stunnel client (those uses TLSv1.2 for Negotiation) are not able to connect . I get below error on the server in logs RSA_sign:digest too big for rsa key:rsa_sign’ How to fix this please? Regards, Vikrant