The champions got the defence of their title off to a losing start last Saturday as they went down 30-22 to Ireland in Cardiff.
"Confidence has been hit by this result, but when we look back at the video, and especially the second half with the chances we created, as long as we can create those opportunities and finish them there is no reason why we can't go out to France and get a result," said Rees.
"We proved how good a team we can be, and we have got to stay tight. I am sure this team will."
France were stunned by Italy 23-18 in their opening match of the tournament on Sunday.