The error occurs usually when
1.When certificate file is not present at the said location (certificate 파일이 지정된 위치에 있는지 확인)
2.When SSL configuration is correct (SSL 설정이 제대로 되었는지 확인)
If both of the above points are not creating an issue (위 두가지가 아니라면..)
3.Then you need to add/update following /etc/apache2/ports.conf from(without quotes) "Listen 443" to "Listen 443 http"
(http-ssl.conf 설정에서 'Listen 443' 설정을 'Listen 443 http' 설정으로 변경)
출처 : http://imranbhullar.blogspot.kr/2012/07/server-should-be-ssl-aware-but-has-no.html
