Why is my computer not reading videos from my camera?

Why is my computer not reading videos from my camera?

I use Windows 2008 and my computer doesn't read videos from my camera. It sees photos no problem, but videos are invisible. It shows only that the memory card is full, but there are no files, yet you can still watch the preview of the videos on the camera itself. It works only with my mom's laptop and only when I pull out the memory card and plug it directly to the laptop, because it doesn't read the videos through the cable.