Whenever I try to restore my old iPhone 3gs, I get error 40 on iTunes.

[Not Really A Hack]

My iPhone 3gs is in recovery mode, and I am trying to restore it, but it will get to the Apple logo with an empty bar under it. Then, it wont go any further and gives me error 40. If anyone could help me with this, I will be extremely grateful.

I am using an official itunes cable, which is directly connected to the computer, and i just tried reinstalling iTunes. I am still getting error 40.

I am going to attach a photo of the last thing displayed on the iPhone screen. ReiBoot does not work.

 

[Tartarus]

First, make sure you are using official Apple charging cable. Also make sure to connect it directly to your computer without any extension cable or hub in the middle.
Second, update your iTunes to the latest version if this is not the case.