It won't let me on sky block since the new minecraft update is this something do with the server or maybe its just me??
Moved thread to the help section. This is due to your client being set on the "Use Latest Version", you can easily fix it in order to play again, by reading this thread here.
I see that your question has been thoroughly answered, so I'll close this. Feel free to report this post for an unlock or simply make a new thread.