Open a new document and place the file in it (make sure Paste Remember Layers is ticked in the Layers palette options if relevant).
Or copy everything and paste it into a new document, to save what you have just created anew.
Some of the file has been lost when saved, and the ending code with it. Your OS has not been nice.
I tried that a few times and always crashed. After your response, I tried it again and it worked fine
You must be my lucky rabbit's foot!
You are welcome, tekkendork.