I am trying to add an environment, but when I press the Add Environment button on the toolbar, I get an error dialog with the message "Parameter is incorrect" and the Environment Information dialog does not appear.

Your Environment Location database that provides the Current Location, Latitude, Longitude and GMT information displayed at the top of the Environment Information dialog has become corrupt. You need to replace it with the original one supplied with your current installation. You can either reinstall your software, or simply visit the Support Downloads section of the EDC website to download a replacement EnvLocation.ldb file.