stuck at the window

I'm right at the beginning. I've been to the inn and am now back at the castle. I must have thrown a hundred rocks at the window, trying all different angles, and nothing is happening! Even when they look like they hit the window. What do I need to do?

Start by aiming below the the window and work your way up

I've also thrown a couple of hundred rocks at the window and took your advice and tried throwing below and working up but still nothing happens. Why would they make it so difficult to complete this task? I don't mind the mind bogglers but this is just too frustrating.

Just take the first big rock and throw it a little below the ledge. Never fails for me