Any DropBox experts please

Lately, although I can access my Dropbox files OK, whenever I try to log in to my Dropbox account from any of my computers, I get the message displayed in attached photo.. I have searched the INET but none of it makes sense to me..I have tried using both Chrome and Firefox browsers.. same results.. Ideas..




If image does not appear.. It says..
Uh oh! Seems like this widget is not configured properly.
localhost domain does not match any Chooser/Server domains. Register app domains on app settings.