Computer cant find SD card

Please help, I have a HP pc and it will not find the SD memory card when i put it in the slot, iv searched the computer and cant find anyway of accessing it, i put the memory card into any other laptop computer it finds it instantly.. where do i go to open it up, its not an option on "my computer" and i keep reading on here to go to device manager which i do, but there are no options on there to do anything, just gives a list of everything and says "working fine" when ever i click anything.. can someone help in detail please