Thanks for you help, i appreciate it, but it didn't work. I uninstall both LDT 2006, Civil Design 3D, deleted the directories on the C drive, ran the batch file and deleted the files in the registry. Reinstalled LDT 2006 and then tried to reinstall Raster Design but still getting the same message. I can't install it on another computer as I only have one license and used it on this computer.