My simple solution to this was to drop the updated file in the Windows Startup folder, along with a batch file that copies it to the Word\Startup folder and then self-destructs. Next time the user reboots their PC, the file is updated, and since it runs at startup, Word is very unlikely to be open in time to interfere. You can also just call a batch file / installer that then asks the user to close all open instances of Word before copying the file.