This could be the reason as your Windows registry is still pointing to a location which no longer exists.mwstevenson wrote:By way of explanation, some time ago I transferred FS9 from C to E drive, which may have something to do with this. Not sure.
Try going to the site linked below and download and run the 'FSX/FS9 Registry Repair Tool'. This will repair your Windows registry so that it points to your new FS2004 location.
http://www.flight1.com/view.asp?page=library
Once you have run the repair tool you should be able to install the 3D lights without issue.