Most of blogspot or blogger author receive a hfeed Warning while they try to verify authorship via rich snippet webmaster tool. Hfeed what does mean “At least one field must be set for HatomFeed” warning.
In simple words, Rich snippet tools try to gather a data from your page in extracted form and when it does not reach your page data, it gives you hfeed warning. Thanks to sumit his blog post encourage me to create a new post about hfeed warning. First think you should know what is hfeed. In one line we can say hfeed is a class of wrapper attribute used in div structure which is a part of hatom microformat schema.
Not sure exact functioning of hfeed but try to explain you what I understand. When any new blog post created or updated, class hfeed tells to web crawler of the search engine for syndicate the content of web page. But this does not mean that without hfeed class your new blog post not syndicated because this does effect your search engine indexing as well there no effect of existing atom feed. You can check my blog atom feed validator.
Solution for Hfeed Warning: Go to blogger -> design-> edit html -> check Expand Widget Templates option, now find hfeed, It should be appear two times, delete hfeed from div structure <div class=’blog-posts hfeed’>. If you get any problem of hcard/hentry missing warning then find hentry it appears one time, <div class=’post hentry uncustomized-post-template’> delete it from div structure. Now save your template and check again in rich snippets tool. This time you done it. If you still persist a problem let me know.