I have the same issue. I tried to deactivate the add-ins, but it didn't help. To confirm my question: is there any way to change the Navigation Pane in Word 2010 so that it defaults to the "Browse the results..." tab instead of the "Browse the headings..." tab? Thanks

Did you also try opening in Safe Mode and seeing what happens when you do so?

View, manage, and install add-ins in Office programs - Support

I know of no simple way to change the behavior of the navigation pane.

Thanks for the quick response. OK, this is interesting. Yes, in safe mode, if I hit Ctrl-F, the Navigation Pane appears with "Browse the results..." selected. But when I reopen Word in normal mode, the Navigation Pane appears and, by default, it shows "Browse the headings..." on top. However, if I then close the Navigation Pane and hit Ctrl-F, the Navigation Pane reappears, but this time with "Browse the results..." on top. The problem is that this will "stick" only for this particular document. When I open a new document, the Navigation Pane immediately goes back to default to "Browse the headings..." This is making searches unwieldy. I simply want to see the search results without having to go through a two step process each time. Is there a way to open a document and have the Navigation Pane appear with the "Browse the results..." tab on top by default? (By the way, I'm using 64-bit Windows 7 OS with 23-bit Office 2010.)