Apple continues to work on fixing a bug introduced in iOS 6.1 that caused Exchange 2010 servers to grind to a halt.
“Apple has identified a fix and will make it available in an upcoming software update,” said a statement on Apple’s support website.
Soon after Apple issued its iOS 6.1 update for the iPhone and iPad in late January, Exchange Server administrators and Office 365 Exchange Online users noticed some bizarre behavior. Users attempting to fetch emails or update their calendars on their newly-updated iPhones and iPads caused log files to swell and CPU and RAM usage on servers running Exchange to spike, severely degrading performance.
For now, Apple prescribes a reset, of sorts. The company is advising users to dig into their Mail, Contacts and Calendars settings, switch Calendars to “off,” wait 10 seconds, and then turn it back on.
In an online support document, Microsoft suggested the fault lies squarely in Apple’s court. “Currently, we recommend that you open an Enterprise Support case with Apple, either through an Enterprise agreement or through a ‘Cross-Platform Integration and Command-Line Interface’ pay-per-incident case to report and diagnose the behavior in iOS 6.1.,” Microsoft said.
Microsoft has, however, created workarounds.
Microsoft recommends having users remove the Exchange account from the affected device and having administrators run the Remove-ActiveSyncDevice cmdlet to square things away on the server-side. After 30 minutes, the user can re-add the Exchange account, but should get a warning against processing Calendar items.
Another option is to throttle iOS 6.1 users, or if all else fails, use the nuclear option. “You can block iOS 6.1 users by using the Exchange Server 2010 Allow/Block/Quarantine feature,” said Microsoft. Until matters are resolved, experts are advising enterprise users to skip this iOS update.
“Apple takes user security very seriously,” An Apple spokesperson said. “We are aware of this issue, and will deliver a fix in a future software update.”