Error code 6 when updating to iOS 7

Hi, I have a fairly new iPhone 4S which had behaved impeccably, bur when I came to update the iOS to 7.0, through iTunes, error code 6 was returned. I had to restore to factory settings, which gave me the new iOS and then I had to restore all apps etc from my last back up. The same thing happened when I updated to iOS 7.02. I have an iPhone running the latest iOS and it's working fine, but if I have to do this everytime there in an incremental iOS update it's going to be really annoying having to set the iPhone aside for a few hours rather than a few minutes.

I've read the Apple Support docs realating to error code 6 and can't really make any sense of it. Also, it's predominantly aimed at Windows users.

Can anyone help me?