A rare but occasional problem in Word 2011 for the Mac is that when opening it may open up what appears every Word document it can find on your computer. There are multiple proposed solutions however often the easiest solution is overlooked when trying to fix the problem. Before trying anything else try this quick fix for Word 2011 Opening up multiple documents at one time:
Close all open Word 2011 documents
Right Click on the Word icon in the doc and click on Quit (if it’s not responding – Force Quit)
Hold down the Shift key and click on the Word Application
If Word opens up a plain blank document the problem should be resolved. This tip may not fix the issue in all cases however.