Windows Vista - http://www.vistaarticles.com
Windows cannot use this hardware device because it has been prepared for safe removal, but it has not been removed from the computer. (Code 47)
http://www.vistaarticles.com/articles/507/1/Windows-cannot-use-this-hardware-device-because-it-has-been-prepared-for-safe-removal%2C-but-it-has-not-been-removed-from-the-computer.-%28Code-47%29
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Published on 11/16/2007
 
Windows cannot use this hardware device because it has been prepared for safe removal, but it has not been removed from the computer. (Code 47)
It has not been removed from the computer. (Code 47)

To fix this problem, unplug this device from the computer and then plug it in again.

The device has been prepared for ejection.

This error code occurs only if the user used the Safe Removal application to prepare the device for removal, or pressed a physical eject button. Restarting the computer brings the device online if the user does not want to eject from the dock.

Unplug the device, and then plug it in again. Alternately, restart the computer to make the device available.