Internet Component Download

Microsoft Internet Component Download (MSICD) is a system service for downloading and installing software from Web sites on the Internet and intranets. This service also provides certificate checking. MSICD is supported by Microsoft Internet Explorer 3.0 and later.

This section contains the overviews and tutorials available for MSICD.

Overviews/Tutorials

Topic Contents
About Distribution Units

Internet software distribution units are packages consisting of a cabinet file (.cab) that contains an INF file and/or an Open Software Description (OSD) file, with or without a software component. One or more distribution units may be needed to distribute a single software component.

About INF File Architecture

An INF file consists of a set of named sections, each containing one or more line items. Each section begins with the name of the section enclosed in square brackets. Sections have a particular purpose (for example, to copy files or add entries to the registry). Each of the line items in a section contributes to the purpose of the section. This article presents the syntax, structure, and processing of INF files.

About Version Changes

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.

Choosing a Packaging and Distribution Method

The purpose of this topic is to help you decide on the appropriate combination of distribution methods for your particular MSICD task. The topic begins by listing the primary options and discussing the relative merits of each. The next section considers the packaging and distribution decision from a problem-based perspective. Links to additional relevant topics are provided throughout.

Enhancing Offline Favorites

Microsoft Active Channel technology is obsolete as of Windows Internet Explorer 7 and should not be used. This article describes the creation and implementation of smart offline Favorites. Using a combination of Channel Definition Format (CDF) and HTML elements, Web authors can enhance the offline browsing experience for users with Microsoft Internet Explorer 5 and later.

How to Automatically Update an ActiveX Control

Software Update Channels enable users to receive automatic updates of Microsoft ActiveX Controls. All a user must do is download an ActiveX control from your site and subscribe to your Software Update Channel. When you release new versions of your ActiveX control, subscribed users visiting a site that uses the new version can choose to receive the update automatically. The new version can be installed immediately, or precached for offline installation later.

How to Package Components for Internet Distribution

Application packaging is the process of creating a container that can install your application on a user's computer. This tutorial explains how to create Internet Component Download packages, called distribution units. When placed on a Web server and referenced from a Web page, distribution units enable users to download and install software from Web sites on the Internet and intranets.

Implementing Internet Component Download

The Internet Component Download service is exposed through a single function, CoGetClassObjectFromURL. This system function is called by an application to download, verify, and install code for an OLE component. The function is used in the implementation of Internet Explorer.

Internet Component Download Tutorials

This section contains the tutorials for Internet Component Download.

Introduction to Internet Component Download

Internet Component Download is a system service for downloading and installing software from Web sites on the Internet and intranets. This service also provides certificate checking. Internet Component Download is supported by Internet Explorer 3.0 and later.

Introduction to Software Update Channels

Active Channel technology is obsolete as of Internet Explorer 7 and should not be used. This article introduces you to the terminology, benefits, and implementation of Software Update Channels. After reading this article, you will understand how easy it is for users to discover and interact with this technology, and you will know how to create your own Software Update Channels. Links to relevant overviews, references, and tutorials are provided at the end of the article.

Managing Versions of a Component

Internet Explorer 3.0 and later provides Internet Component Download services that enable users to download software components from the Internet and intranets. The component's file version is used to control updates. This article explains how to manage the distribution of different versions of the same component.

Publishing Application Updates on the Web

This article describes how to publish updates to applications on the Web.

Registry Details

The Internet Component Download service keeps registry entries for every new downloaded component. These registry entries will be useful for writing a utility for cleaning up the code storage or for migrating the Internet Component Download service to use a code cache rather than a permanent store.

Updating Software with New Versions

Version is a 64-bit number that can be broken up into four components, and is specified for Internet Component Download as a,b,c,d, with most significant to least significant listed left to right.

Using Catalog Files

When more than one distribution unit is required to distribute a component using Internet Component Download, a catalog file can be used to create an association of the required distribution units.

Using Hooks

A hook is a way to override or customize the installation process of one or more pieces required for a component. There are two types of hooks—unconditional and conditional.

Using INF Files

An information file (.inf) provides installation instructions that the Internet Component Download service provided in Internet Explorer 3.0 or later uses to install and register software components downloaded from the Internet, as well as any files required by the components. The INF file is a text file that specifies the files that need to be present or downloaded for your component to run.