Microsoft: Yahoo Mail is Windows Phones' Data Hog

Microsoft confirmed this week what the rumor mill has been saying for a month -- large amounts of unbidden data traffic to and from some consumers' Windows Phone 7 handsets are due to problems with Yahoo Mail.

Up until now, Microsoft (NASDAQ: MSFT) officials had been saying only that the problem was with an app provided by a third party, and that it was working with that company on a remedy. However, Microsoft didn't say who it was, initially. Now it's official that the culprit is Yahoo (NASDAQ: YHOO).

"We have determined that an inefficiency exists in the synchronization of e-mail between the Windows Phone Mail client and Yahoo Mail," a Microsoft spokesperson said in an email to InternetNews.com.

"This inefficiency can result in larger than expected data usage for a very small percentage of users," the spokesperson added. Microsoft has said the numbers of affected users is in "low single-digits."

Last week, Microsoft announced that more than 2 million Windows Phone 7 handsets were sold since they became available in the U.S. in early November.

The first reports of usage of large amounts of data bandwidth came to light in late December and early January, about the time that consumers who got the new phones around the holidays began receiving their first bills from AT&T (NYSE: T). Some reported that they saw a lot of data bandwidth usage that they hadn't expected -- and claimed that they hadn't used.

Initial reports cropped up from users who complained on tech blogger Paul Thurrott's tech enthusiasts' SuperSite for Windows in early January.

"With this phone I do not stream, I hardly surf the Internet, I mostly have the location services turned off," said a purchaser named Julie G. in an email to the SuperSite mailbag. "On December 22nd I received an email from AT&T saying that I was close to my 2 GB data limit which truly shocked me as I feel I do not use data that much."

After a brief investigation, Microsoft acknowledged there was a problem but did not identify the app causing the questionable data transfers.

Despite the competition between the two companies' free email services, Microsoft may have remained quiet until now due to their recently implemented deal for Microsoft to provide the Bing search technologies on Yahoo sites in return for a share of the ad revenue.

A patch is in the works.

"Microsoft and Yahoo have worked together to identify a fix, which will be rolled out in the coming weeks," the spokesperson said. The company has not yet said when that patch will arrive, but Microsoft has said that it has an update to the Windows Phone 7 software pending.

An email requesting comment from Yahoo was not returned in time for publication

Stuart J. Johnston is a contributing writer at InternetNews.com, the news service of Internet.com, the network for technology professionals. Follow him on Twitter @stuartj1000.


Microsoft, wireless, mobile, Windows Phone 7, Yahoo Mail