Windows Mobile 6.5 IE Mobile User-Agent Strings

This article details the default user-agent strings transmitted by Internet Explorer Mobile on devices running Windows Mobile 6.5. It outlines the core structure of these strings, contrasts the default mobile rendering mode with the optional desktop view, and explains the specific browser tokens used during HTTP requests.

Windows Mobile 6.5 included Internet Explorer Mobile 6 (sometimes referred to as IE Mobile 6), which introduced a desktop-derived layout engine alongside two distinct viewing profiles: Mobile View and Desktop View. Depending on the active mode selected by the user or preset by the operating system, the browser transmitted different default User-Agent (UA) headers to web servers.

Default Mobile View User-Agent String

By default, Internet Explorer Mobile operated in Mobile View to request optimized mobile content. The base default User-Agent string sent to servers was:

Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; IEMobile 8.12; MSIEMobile 6.0)

In some build releases and OEM configurations, the version token was simplified or updated according to the specific software build:

Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; IEMobile 6.12)

Key tokens in this string include:

  • Mozilla/4.0: Standard base compatibility token indicating general compatibility with Mozilla-based web standards.
  • compatible; MSIE 6.0: Denotes compatibility with the desktop Internet Explorer 6 layout and rendering engine.
  • Windows CE: The underlying kernel architecture used by Windows Mobile 6.5.
  • IEMobile 8.12 (or 6.12): Identifies the browser as Internet Explorer Mobile along with the internal version/build number.
  • MSIEMobile 6.0: Secondary identifier specifying the mobile engine version.

Desktop View User-Agent String

Users could switch the browser mode to Desktop View to request full desktop websites. When Desktop View was enabled, IE Mobile masked itself as a standard desktop client on Windows XP:

Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)

Key components of this string include:

  • Windows NT 5.1: Masks the operating system identity as desktop Windows XP.
  • SV1: "Security Version 1," indicating Windows XP Service Pack 2 (SP2) security enhancements.

OEM and Hardware Customizations

Device manufacturers (such as HTC, Samsung, or HP) and telecommunication carriers routinely prepended or appended hardware identifiers, language codes, and screen resolution details to the default string.

A fully qualified, real-world User-Agent string from a commercial Windows Mobile 6.5 device often resembled:

HTC_Touch_Pro2_T7373 Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; IEMobile 8.12; MSIEMobile 6.0)

Or with resolution and regional tokens:

Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; IEMobile 8.12; MSIEMobile 6.0; 480x800; PPC)
  • PPC: Identified the device as a Pocket PC platform.
  • 480x800: Disclosed the physical or viewport screen resolution to aid in server-side layout optimization.