My computer died while I was working on a quest gamebook. Now, when I try to reopen the gamebook, it says "*Failed to load game due to the following errors: Invalid XML: Root element is missing." Is there a way for me to get back into my gamebook?

First, make a copy of the file, in case you mess up.

You will need to use a text editor to modify the file. I would suggest creating a new game and seeing what that looks like in the text editor first - especially the first few lines and the last one. Then replicate that in the damaged file. Then try to open the file up in a browser like Chrome, it will probably say if there are errors and point you to where in the file.