I would normally tell you to Google it or search the forum yourself rather than expect other people to do the work, but as I am bit bored I'll make an exception this time.
HDCP is a system implemented by TV providers to stop you recording their HD protected content. If they sense you are using an HDMI cable to feed the TV and you have a third-party video recorder (or, unfortunately, a Slingbox), attached to the component output then they will block the component video. The solution is to completely remove the HDMI cable and feed the TV from the Component OUT of the Slingbox.
Again you haven't really told us anything about your setup so all this has to be guesswork on my part. You really should give us more information if you genuinely want help. And you really should research this yourself anyway to get a better understanding. There are hundreds of posts on this forum about HDCP and Google will drown you in information.