My computer and iTunes do not recognize my iPhone?

Background:
I used an old laptop and ipod touch to listen, buy, transfer, etc. All my music. I just got an iPhone 4 a couple days ago and wanted to start all over with new music and everything, so I downloaded iTunes on my self-built desktop that is basically only used for gaming. There's almost nothing on this computer except for what came with it, some video games, and now iTunes. I don't know if I'm missing some software that allows iPhones to be detected or what.

Problem:
For some reason when I plug in my iPhone to my computer, nothing happens. It doesn't charge, it doesn't pop up on iTunes… Nothing. The USB ports all work with anything else, just not this iPhone. The green light next to the USB port even lights up when I plug it in, but nothing in this computer recognizes it.

I have already tried going through My Computer > Device Manager > Mobile Device, I've tried restarting the phone and computer, I have uninstalled and re-installed iTunes. At this point I have no idea about what the problem is.

Any help would be greatly appreciated!

Did you clean up the registry before and after uninstalling and reinstalling? Installing a new copy over an old copy can cause registry problems with some applications that require pc registry clean up after the uninstall process. Windows Add/Remove does not do that step. This article can help: http://zardozz.com/zz/2010/11/a-perfect-software-uninstaller.html/ Often Invalid or corrupt entries in the dynamic link library (DLL) section of the registry can cause serious application failures like you are having. Using a good registry clean up program if you have one first to restore and repair any damaged or corrupted registry keys will stop these typically frustrating and confusing DLL conflict nightmares.

Never try and fix the PC registry by hand unless you know 100% what you are doing! Trying it manually without without using good automated registry cleanup software is a recipe for a pc disaster! I hope this info helps - also check how to uninstall software properly at: http://uninstallmysoftware.com where you can find more help.