Hello LET,
The Chinese government firewall as of today is actively blocking anyone using a free StartCom StartSSL certificate on their server. Any IP address that is serving a free StartCom StartSSL certificate will be blocked automatically by the Chinese firewall now.
The only solution to this problem is to immediately stop using a free StartCom StartSSL certificate on your server. This will immediately solve the problem and your IP will be unblocked instantly by the Chinese government firewall. Changing IP addresses will not resolve the problem, only the removal of free Startcom StartSSL certificates resolves the problem. We have had several of our clients in China confirm to us this resolves their problem.
If you want to use SSL and have your server reachable within China, you cannot use a free StartCom StartSSL certificate on your IP address at all, or all traffic to that IP address will be blocked in China.
Thought I would post this here since a lot of VPS users in the Lowendbox community may be affected by this.