Why do I keep getting kicked to a Google error page when I try to view my yahoo mail? Its making me NUTS!?

I get an error message which then sends me to a search page with a message like: Sorry, we couldn't find http://l.yimg.comnofiledartiframe.html/%blahblahblahetcetcetc. It does not happen every time I try to use my account and seems worse in the early morning or late afternoons. Anyone else having this problem?