Dear Sirs, I have more information. I had version 6.24 and according to the PVsyst update the last available version is 6.31. After upgrading to 6.31 and keeping version 6.24, the status of the 6.24 is PREMIUM and 6.31 is TRIAL. Should I update without keeping the 6.24 or can I keep both? Thanks. Regards, Jesús Escudero Solís