Optio S50 - can't transfer from camera to pc

I recently bought a Pentax S50 digital zoom camera.
After installing the supplied software, and setting the USB section of the camera to PC as instructed, I am unable to transfer the images from the camera to my PC. I have installed direct X and quicktime which the software suggested.
However, when I connect the camera via USB, the camera seems to turn itself off within seconds and there is no time to download anything. I have checked the batteries and they are fully charged. I keep getting the message: There was an error copying the files.
I am not using an adapter to override the batteries, a) because I don't have one, and b) I only have 6 images to transfer.
As there are no troubleshooting pages in your manuals, I am hoping that you can give me some guidance.
I am using Windows XP
Hope someone can help

By far the most efficient way to transfer images to the PC is to buy a card reader. You can then remove the card from the camera, insert it into the card reader and you will be able to access the images easily. Card readers are very inexpensive and well worth buying.

Not quite the answer to your question, but certainly a way around the problem!

What kind of batteries are you using, what's their capacity?

I am using uniross recharge batteries - green ones AA

How many milliamps per hour (mah) are they?