The term 'invalid request' in your Wordpress post is brought up by Mismatch in redirect_uri error. To fix this start by, visiting plugins and de-activate Jetpack. Secondly, download a fresh install of Jetpack from http://jetpack.me/. Next, then go to ADD PLUGINS and navigate to the ZIP file that you've just downloaded. Finally, once installed, activate it and you should be able to complete the process. Read more ideas from http://wordpress.org/support/topic/connecting-jetpack-to-wordpresscom-error.