Microsoft is blaming Yahoo for a mobile "data drain," which appears to be affecting a small number of Windows Phone 7 devices. "Microsoft suggested an 'inefficiency' between Yahoo Mail and the Windows
Phone Mail client is causing Windows Phone 7's unexplained data drain for some users,"
eWeek reports. Microsoft has spent the past few weeks investigating
complaints of smartphones "devouring" users' data, even when not running apps or surfing the Web. Late last month, the software giant claimed to have discovered the culprit. Rafael Rivera, proprietor
of the Within Windows blog, wrote this week that he discovered Yahoo's Internet Message Access Protocol server not responding correctly to Windows Phone's FETCH requests. "That may not look like much
but sandwich the extra bytes with encryption and multiply the size of each chunk by the number of emails in your box (or folder) ... yeah. Scary," Rivera wrote. Shortly thereafter, Microsoft
programmer Paul Thurrott confirmed Rivera's report.