Can't trap some redirections

[markjl]

Looking at webmaster tools, I get these 2 pages as not found

 

 

mjlvideo.fr/fr/content/9-location-de-materiel

mjlvideo.fr/fr/cassettes-hi8/19-cassette-hi8-45-min.html

 

However even after adding a redirect 301, I get a page saying product not found

 

Il y a 1 erreur :

• produit introuvable
  

 

There are a lot of others though that I can trap and redirect.

 

Any thoughts? Thanks

Edited August 25, 2012 by markjl (see edit history)