Using PS elements I worked on a photo used "file" "save as" then ticked copy and chose the format JPEG, it said that it had to be saved as a copy which is what I wanted anyway then prompted me to choose file size which I did and all seemed well. However when I tried to open it again in Elements there was no thumbnail of it in the folder, just the file name and a blank file image. It said that it could not open because it was the wrong file type. How can Photoshop save a file of a type which it then cannot open?
I was very careful not to do that. By default Elements will choose to save as a PSD file so it is a concious decision to change this to jpeg. It just seems odd that there is even a choice of file within Photoshop that results in a format it can't then open another time.