denede19 on "W3 Total Cache |Leverage browser caching|"

Hope someone could help me with this.
On Page Speed or YSlow it says that i have grade F ib Leverage browser caching... and they says to increse cache on several image types for at least 1 week; it says that i have it for 1 day
I went on Browser Cache and set it to 1 week and after i empty all caches and did the test again, it still shows that i have it for 1 day.
Set expires-header is checked, last-modified header is checked, eTag is checked, W3 Total Cache header is checked, lifetime is set to 604800 seconds.

http://wordpress.org/extend/plugins/w3-total-cache/