(1) I have already solved the problem. I received an update from NCH for WavePad, but the update did not indicate that it would require an additional fee at the expiration of the trial period. So I managed to locate the old version, I reinstalled it, and all is well now. I just wish that NCH didn't release "updates" that are going to require an additional fee.
(2) Regarding your suggestion to use Google, I didn't know that Google had a sound editing program. Where did you find that?????