FeedYes and MyYahoo|
Currently, FeedYes feeds are not recognized by MyYahoo. All other readers do accept FeedYes feeds, and the feeds are all valid. We are looking into this and hope to solve this problem quickly. Anyone who has experience with this problem, and knows how to solve it, please let us know.
Issue has been solved. MyYahoo normally accepts FeedYes feeds again, within one click.