dll for disconnecting a device needed

What I need is a dll to disconnect a device from the computer. The only device that would be disconnected is the one that is an external hard drive. The purpose of this is to put into my programs so when the program is finished copying files, then I don't have to goto safely remove hardware and manually do so. The parameter would be the drive letter. Then it will disconnect the drive so its safe to remove the USB cable. Should be a function that returns true, false. If it was successful, it would return true. If not, then it would return false. Must be COM enabled and be called from VB. Can be done in any language that supports COM and can be called from VB. ## Deliverables The compiled dll and the source code of the work completed. ## Platform Windows XP Home Edition.