Yes you can. Click on the office button to open the main menu. Click on Word options. Then click on customize. In the left column, under chose commands from, select all commands and from the list beneath select save all. Click on the arrow between the two columns so that this command goes into the Customize quick access tool bar. That’s all. From now on you will only have to click on the new icon (three floppies) placed on the quick access tool bar (generally above the ribbon) to save all open files without asking for confirmation, provided they already have a file name. Good luck!