Hi Tony,
I found two discussion forum threads addressing a similar issue. Please take a look at these and let me know if you still have problems.
http://forums.ni.com/ni/board/message?board.id=170&message.id=26765&requireLogin=False
http://forums.ni.com/ni/board/message?board.id=170&message.id=16608&requireLogin=False
Ankita