I went to use my SD card reader last week and noticed it was no longer showing up in the COMPUTER screen. I started to check into the problem and when I tried to start the driver in Device Manager I received "This device cannot start (code 10). I ran the "Check for new Solutions" and was advised to reinstall the driver. Attempting to reinstall the driver returned "You have the latest driver available for this device" . I uninstalled the driver and ran a reinstall out to the Microsoft database which did reinstall the driver. The same Code 10 message still came back. At this point, I started searching the various Microsoft forums this problem and found one that was similar for an external hard drive that wouldn't show up even though it had connected and should have been usable. The advice given to correct this problem was to go to the disk manager screen and assign a drive letter to the device.
Right click "My Computer" Left click on "Manage" Double click "Storage" Double click "Disk Management" All connected devices displayed. My card reader had no drive letter assigned. When I clicked on it, the system automatically assigned a drive letter and the card reader is now working. It was hard to locate anything specific about the Code 10 message, so I thought I'd post this in case anyone ever runs into this problem.