Have a weird yahoo search problem

Yahoo dropped my www. listing and now uses only http://

[Jessica]

For several months i was #1 for a great keyword.
My site appeard in search Yahoo results like this: [domain.net...]

Now after the recent update, yahoo has dropped the www. from my domain and the listing appears as [domain.net...] - it dripped to position #10 too.

Any idea what could be the problem?

[jdwaverly]

Things to Check:

Do you use absolute links (http://www.mydomain.com/page.html) or relative links on your website internal navigation?

Do you 301 redirect mydomain.com to www.mydomain.com?

Are people linking to you as mydomain.com or www.mydomain.com?