Hello, Thanks for your guide. Here's my exact steps: First, I need to make a "valid" crt file. I run this command: cat mysite_com.crt AddTrustExternalCARoot.crt UTNAddTrustServerCA.crt PositiveSSLCA.crt >> new_mysite_com.crt Last, change nginx.conf: ssl_certificate /usr/local/nginx/new_mysite_com.crt; ssl_certificate_key /usr/local/nginx/mysite_com.key; mysite_by nttalex - How to...