Microsoft has released updates for its iOS and Android Outlook applications, following widespread concerns about security.
The updates aim to fix problems in the Outlook applications' security and enterprise management controls, and include new PIN Lock and IMAP support.
The flaw meant that key features such as passcode or encryption policies had no effect on smartphones or tablets running the apps.
"Outlook now implements password enforcement using Exchange ActiveSync. If your company email policy requires that devices have a password in order to sync mail, Outlook will enforce this at the device level," explained Microsoft.
The upgrade offers different changes for Android and iOS. Outlook will check on iOS devices to make sure a passcode is properly set.
"In the event that a passcode is not set, it will prompt users to set one up in iOS settings. Until the passcode is set up, the user will be unable to access Outlook," the firm said.
"On Android devices, Outlook will enforce screen lock rules. Further, Google provides controls that allow Outlook to honour additional Office 365 and Exchange policies regarding password length and complexity and the number of allowable screen-unlock attempts before wiping the phone."
The iOS version will also turn encryption on by default for Outlook users, while the Android app will "encourage storage encryption if it is not enabled".
The IMAP upgrade means that users can now synchronise mail from previously unsupported email providers, including AOL.com and Comcast.net, to the Outlook app.
The update follows widespread concerns about the security of Outlook for iOS and Android.
Microsoft launched the apps in January. They were labelled a "security nightmare" soon after when IBM researcher Rene Winkelmeyer reported finding several faults.
Microsoft then announced upgrade plans designed to shake off the apps' insecure reputation.
Upgrades on the horizon include support for Microsoft Intune mobile device management, and the ability to move Outlook's cloud service from Amazon Web Services to Microsoft Azure.
Microsoft also pledged to support local syncing of contacts, remove the ‘Preview' label from Outlook for Android, improve localisation for all 30 supported languages, and provide more documentation for Outlook's architecture, security and administration controls.
The news follows the discovery of several high-profile attacks targeting mobile devices. Kaspersky reported earlier on Wednesday that it had uncovered the malicious Desert Falcon campaign aimed at Windows and Android users.
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