Back in the old days you would often find files that were caught in a shutdown in the temp folder C:/Windows/Temp, often the files would have the same file name, but instead of "Filename.doc" they would be called "Filename.TMP" or sometimes "Filename.~MP".
Do a search for the filename (If you had saved it at sometime), make sure you search the whole of C: drive and try a wildcard so if your file was called "Letter.Doc" do the search as "Letter.* ", the asterisk tells Windows to search for any file regardless of extension with the name "letter".
If you find it, make a copy of it and try opening the copy, that way if anything goes wrong you still have the original.
If you hadn't saved it at anytime, you may have a problem.
I admit I haven't had to do any of this for a good few years so only going from memory.
Join up if you want to reply.