Thanks, that was very clear but it didn't work! Still does not open Wav or Mp3 files. I wonder if the problem is that I paid for and installed Wavepad on my old PC, used it for a while in Demo mode on the new PC, then remembered I had paid for full access and put in my Registration Code. I was told I had to pay another $22 or so to upgrade. I did this, and was given a new Registration Code. When I've deleted and reinstalled several times, I have only used the new Reg Code. Should I use my original Code, then use the new one when prompted to do so? Your advice would be much appreciated. Thanks and regards. Peter