Tarbat,
Seems to be working now ok. I do have another query, however. How do I access the database to enable me to make manual changes. When I go into C:\Program Files\AirNav Systems\AirNav RadarBox 2009, the data file folder comes up amongst others. If I then click on this folder, I then get a number of data files including one titled NavData and another titled NavData.db3.bak but when I click to open them they don't open but instead I get a message asking for a particular program to open them. Are these the correct files to get into the database and, if so, what program opens them.