Well, I open Zotero preferences and choose to install the Word plug-in. It installs successfully. Then I open Word and choose new document. I don't see the Zotero toolbar! Then when I go to the Word menu (top left), Word just crashes. If I remove the plug-in from the Office folder (Startup>Word), Word behaves normally.

See https://www.zotero.org/support/word_processor_plugin_troubleshooting#zotero_toolbar_doesn_t_appear and follow-up links. When you say "Word just crashes", do you get an error message of some sort? What exactly happens?

Could it be because I was using an external monitor that is now not connected?

I sent the crash log by e-mail.

I tried all that was related to Word. Zotero add-in shows in Tools>Templates and Add-ins and it shows and is enabled in View>Toolbars. I just can't see it!