Windows Mobile users are enterprise users business environments were targeted. With Server Search on Microsoft Exchange 2007, Out of Office Replies with Microsoft Exchange 2007, and search ability for contacts in an Exchange Server Address Book being implemented. To aid development for programmers, .NET Compact Framework v2 SP2 is now preinstalled with the OS. Developers and users also have access to Microsoft SQL Server 2005 Compact Edition for storage and retrieval of information. AJAX, JavaScript, and XMLDOM support were added to Internet Explorer Mobile along with improved devicewide Internet Sharing. Communication abilities were further enhanced with a new Microsoft Bluetooth Stack and VoIP (Internet calling) support with acoustic echo cancellation and MSRT audio codec. To improve security Microsoft added Storage Card Encryption so that encryption keys are lost if device is cold-booted. Further updates both, security and feature, can now also be provided using Operating System Live Update. Among other improvements: 320×320 and 800×480 (WVGA) screen resolution support (The S01SH or "Em One" by Sharp was the first and only device to have an 800×480 screen on WM5), Improved Remote Desktop access (available for only certain Pocket PCs), Customer Feedback option, Smartfilter for searching within programs and Unlicensed Mobile Access (UMA) support for select operators. Windows Mobile 6.1 Windows Mobile 6.1 was announced April 1, 2008, and was based on the Windows CE 5.x kernel. It is a minor upgrade to the Windows Mobile 6 platform with various performance enhancements and a redesigned Home screen featuring horizontal tiles that expand on clicking to display more information, although this new home screen is featured only on Windows Mobile Standard edition. This was not supported in the Professional edition. Several other changes such as threaded SMS, full page zooming in Internet Explorer and 'Domain Enroll' were also added, along with a "mobile" version of the Microsoft OneNote program and an interactive "Getting Started" wizard. Domain Enroll is functionality to connect the device to System Center Mobile Device Manager 2008, a product to manage mobile devices. Windows Mobile 6.1 also had improved bandwidth efficiency in its push-email protocol ActiveSync up to 40%; this considerably improved battery life in many devices. Aside from the visual and feature distinctions, the underlying CE versions can be used to differentiate WM 6.0 from WM 6.1. The version of Windows CE in WM 6.0 is 5.2.*, where the third and final number being a four-digit build ID (e.g.