Many models of PC card readers do not work with "high capacity" formats. For example, a memory card reader capable of reading a 1 GB Secure Digital (SD) card might not read from a 16 GB SDHC card.
The computer might lock up when an SDHC card is inserted into a card reader that does not support SDHC. To immediately fix the lock-up, double-click the Safely Remove Hardware icon, (in the notification area in the lower right corner of the screen), select the USB card reader, and then click Stop. The card reader will not work until the computer is restarted. You can now safely remove the memory card and use the computer for other activities.
To use your higher capacity memory card without locking up the computer, do one of the following:
If you are using the card in a camera or other device, you can attach the device to the computer using a USB or FireWire cable. When connected, most devices appear in Windows as a Removable Disk and can be used in the same way as the card reader.
Use a USB memory card reading device that plugs into any open USB port. Make sure the USB device can read SDHC. These devices are inexpensive and can be used in any computer that has a USB port.
Figure : SDCH to USB card reader adapter