Apple is set to release an upcoming software update to fix a bug affecting Microsoft Exchange accounts on devices running iOS 6.1.
When you respond to an exception to a recurring calendar event with a Microsoft Exchange account on a device running iOS 6.1, the device may begin to generate excessive communication with Microsoft Exchange Server. You may notice increased network activity or reduced battery life on the iOS device. This extra network activity will be shown in the logs on Exchange Server and it may lead to the server blocking the iOS device. This can occur with iOS 6.1 and Microsoft Exchange 2010 SP1 or later, or Microsoft Exchange Online (Office365).
As noted by Apple, an exception is defined as “a change to a single instance of a repeating calendar event.”
Apple promises to fix the issue through an upcoming software update. Presumably, it’s an incremental update to iOS 6.1, which was released a little over a couple of weeks ago.
Until that update arrives, you can avoid the bug by not responding to an exception to a recurring event on your iDevice.
Notably, the upcoming update is not the first remedial patch released for iOS 6.1. Just last Monday, Apple released iOS 6.1.1 in order to fix an issue that impacts cellular performance and reliability on the iPhone 4S.