Why wont my iphone upload pics to my computer?

When I plug my iphone4 up to my computer, the lil box pops up and asks me if I want to upload videos and pics but when I click on it to do so, it says no pics or videos were found. It just started doing this, I have uploaded pics in the past from my phone with no problem but now its not letting me. Please help… Thanks!

You may try iPod/iPad/iPhone transfer software, it's a nice iTunes alternative that can help you upload music and video to iPod/iPad/iPhone, I always use it to sync my iPod when my iTunes can't recognize my iPod, it's easy to use and works pretty well
http://welcometojenelleshouse.xanga.com/766907341/ipodiphoneipad-to-computer-transfer-review/

I have had the same problem and this still hasnt helped i have took it to a shop and they said nothing is the matter anyone else can help me please could you let me know thanks x