Start by removing the unknown device where it appears in the Device Manager (System Properties, Hardware).
Consult the camera's CD and any other information; there might be a README.TXT file on the root of the CD for example. You may need to start a software installation from the CD and not connect the hardware until prompted.
If that route doesn't work, try plugging in the camera again with the CD handy. There should be a folder in the CD for drivers by OS type. You ought to manually be able to instruct the 'unknown device' (in Device Manager) to get drivers from the CD which should get it working.
Edited by pchartwell, 22 June 2005 - 09:21 AM.