lisarace

I have a sony computer,and a sony camera. I usually use the USB cable to put
pictures onto my computer but decided to use my Memory Stick adaptor that
came with my comera. When I put it into the memory stick slot the access
media light does not come on and it tells me to insert a memory disk into the
memory disk E. For some reason it is not detecting it at all. Why is this?
It's all compatable. Thanks.