iPhone will do nothing when i click backup button in iTunes

So i have an iphone 4s and i had previously backed it up to my previous laptop (which i still have and is still working). So since it was getting really slow and old, i decided to use another laptop to backup my phone and to continue to use itunes there in the future. However when i had plugged it in to backup to my new laptop, it simply loads for about a second and then stops. Nothing happens. I tried changing some preferences however that didnt work.

I would just like to use it to sync some more songs however when it says how much space is left and the audio,apps,etc taking up that space, it just classifies it all as other. For example say i had 3gb of music and 1 gb of apps and 4gb free space. It will just say 4gb Other and 4gb free.

Im not sure what to do as i only want to use my new laptop for my future syncing with itunes. Any help is greatly appreciated!!!!!