I had this problem and it was a royal pain in the A** for me too. I tried all the fixes which of course didn't work, then some smart Alecky kid comes along with this fix which I tried and it worked. I doubt it will work for everyone, laptop users in paticular, but hey, like I said it worked for me and my desktop. Now it may sound silly but this is what I did. Uninstalled the device in device manager which had an error code 43 next to it. Shut the machine down. disconnected the power cord. Press the on button a couple of times for good measure, (to make sure the capacitors are completely dischared) you may notice a brief LED flash or Fan whirl when you first press the on button, even though the power cord has been removed, this is residiual power left behind being discharged. Leave the machine for a minute or two just to make sure. Boot the machine up, then try the card reader once you have logged in.
This worked for me. For some unknown reason there was an error of the device during installation, and even though I had removed it from device manager residual power wasn't allowing the process to be completed properly. Removing the device and allowing the power power to drain completely from the system allowed the device to be reomved properly. I expect that there is a way to remove it via the registry, but like I said, if it can be done this way, you may save yourself a headache. Removing the battery if you have a laptop may also do the trick. Just make sure you remove the faulty device from device manager first.
This happened to both my son's and my windows 7 64bit machines, and this fix did the trick. Hope this helps you guys.