Windows 7: Yahoo, Microsoft finally 'fess up to Windows Phone 7 data usage

Microsoft and Yahoo have finally acknowledged that Yahoo is, as has long been suspected, culpable for Windows Phone 7's excessive data usage. Microsoft admitted to a problem a couple of weeks ago, faulting an a third-party service but infuriatingly refusing to specify which third party.

This silence was unfortunate, as it left users with no good way to avoid the problem: given the potential to run up substantial bills, this was indefensibly irresponsible of Microsoft. Now that Yahoo! Mail has been confirmed as the problematic provider, users can mitigate the issue by setting any Yahoo accounts to check for mail only manually.

The confession came after the companies were left with no other option; investigative work by Rafael Rivera demonstrated that Yahoo was sending 25 times more data than other IMAP mail providers whenever the phone interrogates the mail server; though the amount of data transferred each time is not enormous, the effect over the span of a month can be many gigabytes of data.