Little issue with OpenSSL for Windows came out recently when I tried to create certificate request. Just after installation when tried to generate cert request got error message:

WARNING: can't open config file: /usr/local/ssl/openssl.cnf
Unable to load config info from /usr/local/ssl/openssl.cnf

Reason was that by default OpenSSL couldn’t find configuration file (even if it was located in same folder as excutable file).

So, to fix it just set environmental variable with information where openssl.cfg file is located:

set OPENSSL_CONF=c:\OpenSSL-Win32\bin\openssl.cfg

You can consider adding this to system environmental variables.