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ActiveSync 4.x Desktop Software Guide


In January 2005, after much speculation of the release a Microsoft Windows Mobile division leak disclosed details of formal work on ActiveSync 4.0.

This document describes ActiveSync Version

ActiveSync 4.x Logo

ActiveSync 4 - History

ActiveSync 4.0 ( BETA emerged as the first evidence of the fourth generation Windows CE sync client on January 5th 2005.

About Box

Little is currently known about ActiveSync 4.0's features or its release. The user interface at this early beta stage has not received significant updates to the 3.8 release which appeared on January 6th 2005. The most significant improvement that can be seen already in the pending ActiveSync release are the modifications to the 'Get Connected' wizard, now renamed the "Synchronisation Setup Wizard".
ActiveSync's synchronisation services now support the direct connection to both Microsoft Outlook on a local PC, or a directly integrated connection with Microsoft Exchange Server. Improvements to the integration with the host Outlook PIM have been made, with the ability - when connecting to a supporting device - to synchronise user photographs in contact entries.

The final ActiveSync 4.0 beta was built on the 4th March 2005 with a version number of ActiveSync 4.0 officially RTM'd at build, but was only released via the web as a Developer Preview release. No formal RTM public redistributable was made available before or at the RTM and launch of Windows Mobile 5.0. Currently the only way to obtain ActiveSync 4.0 is on the CD which ships with Windows Mobile 5.0 devices or ROM upgrades.
The ActiveSync 4.0 build shipping on CD with Windows Mobile 5.0 device's is

ActiveSync 4.0 changed the ActiveSync formula considerably. For the first time, users were able to specify where they installed the program to on their computers file system. More fundimental changes on the release revolved around the removal of on-personal area connectivity options from the synchronisation mix. The main reason for the removal of these features on the face of it was to reimpliment them in the corporate server solution Exchange 2003's new Windows Mobile connectivity module, leaving individual users or non-Exchange commercial users with little choice as 4.0 became mandatory for all new Windows Mobile 5.0 devices.

Services for connections with Microsoft SQL server are included, along with a Synchronisation update for Windows Media Player 10 (KB894476 - not available at the time or writing) which allows you to access the auto synchronisation functionality from the Windows Media device manager directly from ActiveSync, without the need to shell out to Windows Media Player itself.

Windows XP SP2 also has an integration update in the form of MS KB890927, this patch changed the USB layer of Windows XP to prevent Remote Network Driver Interface Specification (RNDIS) connected devices from locking up the PC when they disconnected. Fortunately, despite this and numerous other fundamental change to the USB layer of ActiveSync, the 4.0 release for many failed to work correctly, introducing new problems. As a result, ActiveSync 4.0 was never formally RTM'd, and never made available to download as a web release.

ActiveSync was released to manufacturing on 18th November 2005 and became the first web reditributable of the ActiveSync 4 generation sync client. ActiveSync is a critical update to ActiveSync 4.0 as Microsoft were forced to silently recall ActiveSync 4.0 due to the discovery of critical show-stopper bugs in the CD release version that was dispatched with the early Windows Mobile 5.0 devices. Despite the recall, OEM's expected Microsoft to honour the release schedule for Windows Mobile 5.0, and when the first lines of devices began to emerge from OEM's, they shipped with the crippled sync client.

Following on from the synchronised platform release of ActiveSync 4.1, ActiveSync was the first formal update relase for ActiveSync 4. The installer for version 4.2 was properly branded as a 4.2 release, and included revised EULA terms.

Changes in the 4.2 release were formally stated by Microsoft as being:

  • Microsoft Outlook Improvements: Resolves issues relating to error code 85010014
  • Proxy/DTPT interaction Improvements: Improved auto configuration of device Connection Manager settings when desktop has no proxy path to the Internet
  • Improved Desktop Pass Thru behavior with ISA proxy failures
  • Partnership improvements: Better resolution of multiple devices with the same name syncing with the same desktop
  • Connectivity Improvements: Better handling of VPN clients (resolve unbinding of protocols from our RNDIS adapter). New auto detection of connectivity failure with user diagnostic alerts

ActiveSync 4.2 also shipped with a new troubleshooter utility, designed to detect and resolve connectivity and synchronisation issues with Windows Mobile devices. The utility, which is available from the Help menu of ActiveSync looks at the system network and firewall configuration, as well as PIM and active connection status to diagnose problems in real-time. At the end of the diagnostic and repair process, the user can opt to transmit the status report to Microsoft for diagnostic purposes, presumably to help improve ActiveSync and the diagnostic tool in future releases.

ActiveSync 4.5 build 5096 was released on the 13th February 2007, and marks the final release of the ActiveSync lineage. ActiveSync has been repleased with the standalone Windows Mobile Device Center program for Windows Vista and the integrated Windows Device Centre in Windows 7.

Confirmed Features (by HPC:Factor)

  • ActiveSync 4.2 is NOT compatible With Windows CE 2.00 or H/PC Professional devices
  • The Visual Studio 2005 development platform when used to compile for Windows CE 5.0 / Windows Mobile 5.0 using debug or live device connections will require ActiveSync 4.0 or higher to be installed with the IDE
  • SP4 & Internet Explorer 6.0 SP1 will be required for installations under Windows 2000
  • SP1 or SP2 will be required under Windows XP
  • SP1 will be required under Windows Server 2003
  • Windows 95, 98, 98SE, Millennium and NT4.0 support has been dropped
    Unsupported OS
  • ActiveSync 4.0 has been wrapped into a MSI installation package; allowing for Group Policy distribution
  • x86, x64 (EM64T & AMD64) and IA64 versions are available
  • The installation footprint of ActiveSync 4.1 is 28MB
  • Bluetooth is now a native connectivity method recognised by the ActiveSync application

Officially Supported Devices:

  • Windows Mobile 2003
  • Windows Mobile 2003 Second Edition
  • Windows Mobile 5.0
  • Windows Mobile 6.0
  • Windows Mobile 6.1
  • Windows Mobile 6.5
  • Pocket PC 2002
  • Smartphone 2002

Unofficially Supported Devices:

  • Handheld PC 2000
  • Pocket PC 2000 (Assumed)
  • Windows CE 4.0 .net
  • Windows CE 4.1 Net
  • Windows CE 4.2 Net
  • Windows CE 5.0

Unsupported Devices:

  • Windows CE 1.0
  • Windows CE 1.01
  • Windows CE 2.0
  • Palm PC 1.0
  • Palm-Size PC 1.1
  • Palm-Size PC 1.2
  • Handheld PC Professional
  • Windows CE 2.10
  • Windows CE 2.11
  • Windows CE 2.12

Speculation on ActiveSync 4.0

Contrary to original expectations, ActiveSync 4.0 has not been simultaneously release to the public with the Windows CE 5.0 based 'Windows Mobile 5.0' release (Magneto). ActiveSync 4.0 is still locked in the Developer Preview release, with Microsoft having made no comment on its progress.
Based on previous trends of ActiveSync codename tie-ups. Speculatively, the ActiveSync 4.0 release could also be under the Magneto banner, although currently the ActiveSync 3.8 code name Medusa is still present in the code (this could be because of code recycling).
For more information on the Magneto release schedule please see the HPC:Factor History of Windows CE document, here.

This document will be updated as Microsoft make more information available.
The information disclosed in this document is based on information correlated unofficially. HPC:Factor makes no claims to the origin of the information. HPC:Factor will not provide copies of leaked screen captured material under any circumstances.
Any information on BETA releases is subject to change at the discretion of the Microsoft Corporation at any time without notice.

System Requirements for Version 4.0 / 4.1 / 4.2 / 4.5

  • Minimum System Processor
    • Pentium 133 MHz or Higher for Windows 2000
    • Pentium 233 MHz or Higher for Windows XP / Windows 2003 Server
    • Pentium 4 2GHz or Higher for Windows Vista
    • Equivalent x86, x64 or IA64 Processor
  • Minimum System Memory
    • 64 MB RAM for Windows 2000
    • 128 MB RAM for Windows XP / Windows 2003 Server
    • 512 MB RAM for Windows Vista
  • 28 MB Hard Disk Space
  • Microsoft Internet Explorer 6.0 SP1 or higher
  • 1 free USB Host Port
  • 1 free 9 or 25 pin communications port for Sync Cable
  • 256 Colour VGA compatible display adapter
  • Keyboard & Pointing device
  • Outlook 2000 or later for PIM synchronisation

Operating System Requirements:

  • Sound Card & Speakers
  • Microsoft 2000, XP (2002) or 2003
  • IrDA compatible Infrared or Fast Infrared port
  • Microsoft Systems Management Server 2.0
  • Microsoft Exchange Server 2003 SP1 for LAN Sync & Push e-mail support


Microsoft ActiveSync is designed for Handheld PC's running Windows CE 3.0 and higher ONLY.

ActiveSync 4.x is designed specifically for use against Windows Mobile 5.0. Unless you have Windows Mobile 5.0 device, or a 64-bit Processor HPC:Factor recommends that all users download and install ActiveSync 3.8.

Software Compatibility

Operating System Compatibility Notes
Windows 3.1x Logo Windows 3.1x No  
Windows NT 3.51 Logo Windows NT 3.51 No  

Windows 95 Logo

Windows 95, A, B, C No Unsupported Code
Windows NT 4.0 Logo Windows NT 4.0 No Windows NT4 support has been dropped
Windows 98 Logo Windows 98 No Windows 9x support has been dropped
Windows 98 SE Logo Windows 98 SE No Windows 9x support has been dropped
Windows 2000 Logo Windows 2000 Yes SP4 & Internet Explorer 6.0 SP1 required
Windows Millennium Logo Windows Millennium No Windows 9x support has been dropped
Windows XP Logo Windows XP Yes SP1 / SP2 required
Windows Server 2003 Logo Windows Server 2003 Yes SP1 required
Windows Vista Logo Windows Vista No Disabled by Application Compatibility
Windows Vista Logo Windows 7 No Disabled by Application Compatibility
Windows Vista Logo Windows Server 2008 No Disabled by Application Compatibility
Windows Vista Logo Windows 8 No Disabled by Application Compatibility
Windows Vista Logo Windows Server 2012 No Disabled by Application Compatibility
Mac OS Logo Mac OS No  
Linux 'Tux' Logo Linux No  
Unix 'BSD' Logo Unix No  

For more information see CESD-S-0021