OK, I've de-installed using the Revo utility as suggested and re-installed and eventually it has worked. I say eventually because I had a different problem when I received the message "It is not possible to dock the media Selector at the current display resolution" on startup of videowave. I searched about this message and found another person who had altered their display settings and then altered them back again thus overcoming the problem. I did the same and I have videowave working again. I was impressed with the Revo utility so thanks for your help with my problem. I suppose we are left a little unsure what caused it in the first place, but if it happens again, I have a way back.