Computer Memory Card Reader Help With Memory Card Reader.. Computer Can Not Detect.?

Help with memory card reader.. computer can not detect.? - computer memory card reader

I bought a 21-in-1 memory card reader and when I plug the computer does not recognize. I clicked on "My Computer" and there is no removable disk icon. He gave me a "New Hardware Found" reserved. What can I do? Computer operating system is Windows Millennium, and that's all I know about him. Need Advice?