Although not 100% sure, 4 would be the RX on the Arduino and should be connected to the TX of the BlueTooth; 7 would be the TX on the Arduino and hould be connected to the RX of the BlueTooth.
So below would be wrong.
Please edit your post #3, select all code and click the </> button to apply code tags; next save your post.
Lastly, your topic has been moved to a more suitable location on the forum. Installation and Troubleshooting is not for problems with (nor for advise on) your project 
See About the IDE 1.x category.