What does it mean that this member has "blocked" me?
It means that he or she does not want you to send messages to him or her.
That's disappointing... Can you tell me why?
No, we really don't know...
OK, but I REALLY have to send him/her a message. Can you help me?
No, we respect our member's right to block the ones they don't want to have contact with, and we do not interfere for any reason.