A fresh test on Thursday confirmed that Yahoo’s IMAP mail bug had been fixed. Per Electronista, Yahoo quietly upgraded its mail servers so that they now respond with only the data they were asked for, rather than the 25 times higher amount they were producing before. Rafael Rivera at Within Windows noted that it had previously sent the entire message header.
The improvement should cure a problem first discovered on Windows Phone 7 that led to a glut of data every time the devices checked mail. Later discoveries found that it also affected at least iPhone owners, but all of them carried the risk of running over bandwidth caps on carriers like AT&T.
Microsoft knew of the cause in Yahoo’s servers weeks after it was found but declined to name it, leaving customers without an idea as to which services to turn off. It instead gave them blanket instructions to turn off automatic mail checks or to disable cellular data. It wasn’t until Rivera investigated himself and confronted Microsoft that it was forced to acknowledge the source.
If you’ve seen any changes in your Yahoo mail on your iPhone, please let us know.