I have just started using the program. However I experience the system locking up a few steps in and the program crashes. Each time I navigate to the location/meteo section and select Australia/Melbourne it fails and shuts down. For other locations it seems to work. The first part of the error description is pasted below. Problem Event Name: APPCRASH Application Name: Pvsyst6.exe Application Version: 6.3.5.0 Application Timestamp: 55118242 Fault Module Name: StackHash_512c IAny suggestions greatly appreciated, Michael