If you connect a USB storage device, such as a flash drive, the device may not appear in the Safely Remove Hardware window when you click the Safely Remove Hardware icon in the notification area.
Figure : Safely Remove Hardware
The USB device may not appear if it was stopped previously and not unplugged from the USB port. Unplug the device, wait about 20 seconds, and then plug the device back in. The device should re-appear in the list. If not, restart the computer and try again.
If the device is a memory card in a USB card reader, restarting the computer should correct the problem. To prevent the problem from occurring in the future, do not use the safely remove hardware icon to remove a memory card. Instead, use Windows to eject the card. The following steps explain how to properly eject memory cards from a card reader:
Insert a memory card when the light on the reader is not flashing. You can have four memory cards inserted, one in each slot, at the same time.
An autoplay window appears. If not, access the card through Windows Explorer.
The memory card has a drive letter associated with it, just like a floppy, CD-ROM drive, or hard drive. Use the memory card as you would use any other drive on the computer. For example, double-click the memory card icon to open a new window showing the files on the CompactFlash card.
When you have finished working with the files on a memory card, right-click the memory card icon and select Eject. The light on the memory card reader should not be ON or flashing when the card is removed from its slot.
Figure : Eject feature in Windows Vista
Figure : Eject feature in Windows XP