where you can find a copy of the Zotero.dotm file.
The correct folder can often be found in the Word preferences:
Click the Microsoft Office Button in the top-left corner (in Word 2010 the “File” tab replaces the Microsoft Office Button), and then click Word Options. Click Advanced. Under General, click File Locations. The Startup folder should be listed there. Select it and click Modify. Placing the cursor in the location bar at the top of the window will allow you to copy the complete path to the Startup folder. Click Cancel to close the dialog.
In Word, open the “Word” menu in the top-left of the screen and select “Preferences”. Click on “File Locations” under “Personal Settings” and click on “Startup” at the bottom of the list. This may list your Startup folder location.
If there is no location listed, the default location is ~/Library/Group Containers/UBF8T346G9.Office/User Content/Startup/Word (i.e., the Library folder within your home directory). The ~/Library folder is hidden by default, but you can open it from the Finder by holding down Option, clicking the Go menu, and selecting Library. You can also press Cmd-Shift-G in Finder and copy the path above to navigate to that folder.
The default location of the startup folder is /Applications/Microsoft Office 2011/Office/Startup/Word. You can open it from the Finder by pressing Cmd-Shift-G and copying in the path or by navigating to it.
If changes you make to the startup folder aren't taking effect, you can confirm that Word isn't set to a different location. In Word, open the “Word” menu in the top-left of the screen and select “Preferences”. Click on “File Locations” under “Personal Settings” and click on “Startup” at the bottom of the list.
On non-English systems or in certain custom setups, these locations may be different.
Word 2000, 2002 (XP), 2003, 2007, and 2010, 2013 under Windows Vista, Windows 7 & 8
Word 2000, 2002 (XP), 2003, 2007, and 2010 under Windows 2000 or XP
Word 2016 for Mac
Word 2011 for Mac