Hotplug.dll error message

Use Win2000 SP4 in a Dell workstation 340.  Recently cloned C drive without a problem (forum helped a lot).

One problem since has come up. Have an error message whenever closing a peripheral device like a card reader or external HD.

When ready to unplug, I go to the icon on the taskbar and right click as always to correctly unplug it and the error message comes up that there is a problem with the hotplug.dll, located in WinNT/System32.

Where would I find this specific file to replace the one that seems to have been corrupted along the way.