Got a mail from March that doesn't appear in the flagged filter, if I go and search for it it's there and it's flagged.

This is annoying, if it doesn't appear in the filter then I think it's been dealt with when it hasn't.

Is there some setting I can change to fix this or something?

EDIT: Also when are you going to update your categories!?  Didn't Windows Live Mail die a long time ago????