HELP: Xbox controller not connecting to my xbox.

[benji232]

I have had my 360 for about 4 years now. I hadn't touched my 360 in about 4 months (because of the wiiU) but I recently decided to order tales of vesperia from Amazon. So I tried to go on my xbox360, but my controller wouldn't connect. The weird thing is that it can open my 360 when I push on the middle button but it then just keeps blinking forever. I tried syncing it which didn't work. I tried changing batteries which also didn't work. 

I doubt my controller is broken because it is capable of opening my 360, it just won't connect to it (which is kinda weird considering it is capable of opening the 360).

Anyways, can anyone help me please?