How the Inventory Collector Works

Applies To: Windows 7, Windows Vista

The Inventory Collector enables you to examine each of your organization's computers, identifying the installed applications, devices, and system information, in order to collect a complete catalog of information. After the data has been collected, you can review all of the information from within the Application Compatibility Manager.

This topic includes:

  • Inventory Collector terminology

  • Inventory Collector processes

  • Inventory Collector data and log files

Inventory Collector Terminology

Term Definition

ACT Log Processing Service

The service that processes the log files uploaded from your client computers, adding the information to your ACT database.

Application Compatibility Manager (ACM)

The user interface (UI) that enables you to view reports based on the Inventory Collector information generated from the ACT database. This is also where you create the data-collection packages (DCPs) used to deploy the Inventory Collector.

Application Compatibility Toolkit (ACT)

A suite of tools that enables software developers, independent software vendors (ISVs), and enterprise IT professionals to determine whether their applications are compatible with a new version of the Windows® operating system, newly released Windows security updates, and new versions of Internet Explorer®.

Application Compatibility Toolkit Data Collector (ACT-DC)

A self-extracting executable (.exe) file containing your configuration manifest and installation file for the data collector and compatibility evaluators. After deployment, ACT-DC installs the compatibility evaluators, maintains their scheduling and data collection, and uploads the issue data to your ACT database.

compatibility evaluator

A command-line program launched by the ACT-DC and configured by the user through the DCP settings. An evaluator might run immediately and exit, or continue to monitor system activity through the duration configured by the user.

compatibility-evaluator definition package

The collection of files and data created by a partner defining a compatibility evaluator.

compatibility-evaluator installation package

The installation package used by the ACT-DC to install a compatibility-evaluator module. The provider of the compatibility evaluator produces the compatibility-evaluator installation package that is included in the compatibility-evaluator definition package.

compatibility-evaluator module

A compatibility-evaluator component that is exposed to the ACT-DC. A compatibility-evaluator module generates data and can have dependencies on other compatibility evaluators.


A part of ACT that specifies the compatibility-evaluator resources and settings.

configuration manifest

A file containing all of the user-configurable settings such as which compatibility evaluators will run, when and how long the compatibility evaluators will run, where to log data, and so on.

data-collection package (DCP)

A Microsoft® Windows® installer (.msi) file created in the ACM for deployment to each of your client computers. Each DCP can include one or more compatibility evaluators, depending on what you are trying to evaluate.

data collector

A set of compatibility-evaluator modules that produce or gather data and then store the data locally in a raw or nearly raw form. All compatibility evaluators act as data collectors, and are installed and deployed by ACT-DC.

evidence file

An XML document that contains a set of evidence gathered by the Inventory Collector and processed by the Bucketizer. A Bucketizer is an executable (.exe) file that processes the raw XML data collected by the Update Compatibility Evaluator (UCE) and sends it to a centralized location.

evidence or indicators

Information used to determine the installed applications on a computer.

inventory component

A component that creates an inventory of applications, application indicators, and system properties for a computer.


A compatibility-evaluator module that takes volumes of raw data and produces data in a format that matches the ACT schema, with extensions supplied by the compatibility-evaluator provider. More than one post-processor might depend on a single data collector, and a post-processor might depend on data from more than one data collector.

Inventory Collector and the ACT-DC Processes

ACT-DC performs the following steps:

  1. Launches the Collect.exe program.

  2. Passes parameters from the configuration manifest or command-line arguments to the Inventory Collector.

  3. Parses and validates the command-line arguments and extracts the Acinv.dll file to a temporary location.

  4. Creates an instance of the IappInventory and the IsystemInventory Component Object Model (COM) interface pointers from Acinv.dll.

  5. Sets properties on the IappInventory and the IsystemInventory interfaces, according to parameters or command-line arguments.

  6. Gathers data by invoking the IappInventory::Populate and the IsystemInventory::Populate methods.

  7. Gets XML representation of the data gathered from the interfaces, by invoking the GetXMLString method.

  8. Combines the XML data and inserts additional information, such as log identification data.

  9. Stores the log data as an .xml file at the indicated log file location and then exits.

Inventory Collector Data and Log Files

The Inventory Collector gathers inventory data from the client computers, including:

  • Log identification. Provides log information to the Inventory Collector, including the application version, the date and time stamp, configured options, and so on.

  • System inventory. Information about the client computer, including the amount of memory, the processor speed, the architecture, and so on.

  • Device inventory. Information about the devices installed on the client computer, including the model, manufacturer, and device class.

  • Software inventory. An inventory of all the evidence for the applications installed on the client computer. This evidence includes system technologies such as Windows Installer, Shell, and so on. The Acinv.dll file does the gathering of this inventory.

See Also


Inventory Collector Technical Reference
Phase 1: Collecting Your Compatibility Data
Microsoft Application Compatibility Toolkit Data Collector (ACT-DC) Technical Reference