Sometimes Zotero does not perform the action we expect.  Common examples are:

• Not downloading a pdf with the browser connector.
• "Updating document" message will not finish in Google Docs.

There are two main reasons why the Zotero browser connector may not download a pdf.

• The Zotero desktop app may not be open.
• There may be an issue with the page itself.  JSTOR, for example, requires that you open a pdf and accept their terms of use before the Zotero browser connector can download pdfs for the rest of the browser session.

Sometimes Google Docs will stop responding and show the "Updating document" message endlessly on a new Google Doc.

• Check “behind” the browser for the Zotero document preferences window or citation box. If you click on Zotero in the task bar or mac version of that, you can bring the document preferences window or red citation box to the front.

• Close/quit, then re-open, both Zotero and browser.
• If you are on a Mac, remember to completely quit (cmd + q shortcut) each program to fully close before re-opening.