About Version Changes

Internet Component Download started with Microsoft Internet Explorer 3.0 and provided a way to download software from the Internet. Internet Component Download was based on an INF file, which specified the attributes of the software that needed to be known for downloading. This early version of Internet Component Download, as implemented by Internet Explorer 3.0, was limited for the following reasons:

  • No support for Java class libraries.
  • No support for stand-alone Java applications.
  • INF files not written according to any standard syntax or grammar.
  • Old distribution units limited in flexibility because they cannot adequately express software dependencies.

Additions to the Internet Component Download mechanism have been made in later versions of Windows Internet Explorer. The following links go to sections that detail the changes made in other versions.

  • Additions in Microsoft Internet Explorer 4.0
  • Changes in Microsoft Internet Explorer 4.01

Additions in Microsoft Internet Explorer 4.0

Microsoft Internet Explorer 4.0 solved the above problems by supporting the Open Software Description (OSD) vocabulary. OSD provides the Internet Component Download mechanism with the ability to download Java applications, Java packages, and Microsoft ActiveX Controls. OSD also provides the ability to handle complex file dependencies that might be spread out over multiple distribution units on the Internet, and it provides automatic installation of missing components. This article covers topics common to both the INF and OSD format of Internet Component Download. For information specific to OSD or INF format, see About OSD File Architecture and Using INF Files.

Changes in Microsoft Internet Explorer 4.01

The following table briefly summarizes the changes between Internet Explorer 4.0 and Microsoft Internet Explorer 4.01.

Feature 4.0 4.01
Advertise new component version yes yes
Precache new component version yes yes
OSD-aware shortcuts no yes
ActiveX control precache yes yes
ActiveX channel upgrade no yes
OSD-based Java install yes yes

Note Internet Explorer 4.0 is able to precache an ActiveX control only if an object tag uses the same code base as the software update channel.