ActiveSync 4.5 增强了 Smartphone 同PC和 Microsoft Exchange 间的安装、协作以及连接能力。此外，这个版本还包括有一个诊断工具，可以扫描电脑和设备，并提供相关的解决方案。ActiveSync 4.5 支持 Smartphone 到桌面或 Tablet PC 的USB、蓝牙和红外连接。
• Supported Mobile Platforms: Microsoft® Windows Mobile® 5.0; Messaging and Security Feature Pack for Microsoft® Windows Mobile® 5.0; Microsoft® Windows Mobile® 2003 Second Edition; Microsoft® Windows Mobile® 2003; Microsoft® Pocket PC 2002, Microsoft® Windows® CE OS version 3.0; Microsoft® Smartphone 2002, Microsoft® Windows® CE OS version 3.0
• Microsoft® Office XP or Microsoft® Office 2003
Microsoft® Outlook® XP, or Microsoft® Outlook® 2003 messaging and collaboration clients required for synchronization to the desktop or portable computer of e-mail, calendar, contacts, tasks, and notes. (Outlook 2003 is recommended)
• Microsoft® Internet Explorer 6.0 or later (required)
• Microsoft® Systems Management Server 2.0