You only needed to do one or the other, not both. You still didn't answer
the question: why did all doc files become dotx files (word 2007 templates)?
If you were using Word 2003 and had doc files, your computer did not even
know about Word 2007 format files. Something must have happened to your
system. Files do not spontaneously change file extensions. Did you move them
on some type of external drive? Did you install something? Have you got a
virus?
Terry