I have set outlook up to retrieve emails from my yahoo account. it takes all
of my emails from yahoo and they land in the in box in outlook. But, when I
click on my outlook inbox I cget an error message that says "unable to
display the foldier. Could not complete the operation. One or more parameter
values are not valid". Which means I can't view the emails once they are in
outlook. Yet outlook does not leave any of them in my yahoo end box.

What do I need to do to display my outlook inbox?
What do I need to do for outlook to take copies of my yahoo emails and leave
the emails in yahoo so that I can also have access to them there.