1) Select the Zotero menu tab at the top, then select "Preferences"
2) A pop-up window will open. There are a number of tabs at the top of the window. Choose the one that says "Sync":
3) In the "Sync" window you will see a section called "File Syncing"
There are two check-off boxes in this section.
UNCHECK THE FIRST ONE that says "Sync attachment files in My Library using Zotero” (leave
the other one checked):
A pop-up window will appear with many options at the top. Choose “Advanced”:
5) On the Advanced screen that opens, choose “Files and Folders” from the tabs that appear there:
6) Look for where it says "Base Directory":
Please DO NOT ADJUST THE DATA DIRECTORY LOCATION!
Set the Base directory to the same folder you set up with Dropbox on your computer.
*Please note that you need to change this base directory on all machines that you plan on using Zotero with so that the attachments can be found.