Sometimes when your computer has crashed while Word is open and in use, Word will take its revenge on its add-ins. Generally this happens without provocation, just MSFT taking its frustrations out on the nearest program.
The symptom is that the program tab, TheFormTool or Doxserá button in the menu bar, has suddenly disappeared following a Word shutdown. This short video takes you through the half-dozen clicks to get back into operation. If nothing else works, you may want to make a manual installation of the program. Instructions on how to accomplish a manual installation are found at http://service.theformtool.com/hc/en-us/articles/212275946-Manual-Installation
tags: video, missing, menu, tab, button, help, not there, install, disappear, menu