This really means, your Excel treats dates only in mm/dd/yy format. So you need to enter dates in this way. For example, when typing 14th of september, use the format
09/14/2013 (or 14-sep-2013).
Yes, We will be doing a permanent redirect from old forum to new forum when anyone try to navigate there. After harvesting any remaining data (user favorites, may be tags), I will close down the old forum.