i have a 15 in one card reader on my windows vista hp computer it will work fine once then. i will safely remove the compact disk and then i try to put a SD card in and it will not read it then i try ed the compact disk and it will not read it also all the removable disks are gone what is the problem
If the card-reader is built-in to your computer, Windows probably still sees it as an external device. When you safely removed or ejected the other device it is possible the Windows disabled your card reader so it could be safely removed (even if it's internal). If it is an external reader, try unplugging it and plugging it back in. If it is an internal reader, try rebooting your computer.
