Yahoo mail going to Windows mail on Vista

I am just changed over my set-up so all my yahoo emails go straight to my new
Windows mail inbox. I went through the process of saving my yahoo preferences
to allow this and then set up my account using my existing yahoo details on
Windows mail. At first all the existing mails in yahoo inbox went straight to
my windows mail inbox but since then no mail seems to get through to my
windows mail inbox and I am still having to access my account via the yahoo
site..Any ideas? Thanks
--
pjryan