OLE/COM Object Viewer

OLE/COM Object Viewer
Name	OLE/COM Object Viewer
Developer	Microsoft
Released	1990s
Latest release	included with Windows SDK
Operating system	Microsoft Windows
License	Proprietary

OLE/COM Object Viewer

The OLE/COM Object Viewer is a Microsoft utility for inspecting Component Object Model interfaces and Object Linking and Embedding registries. It assists developers working with Windows APIs, system libraries, and binary interfaces by enumerating classes, interfaces, type libraries, and monikers. Software engineers from organizations such as Microsoft, Intel, IBM, and Intel partner ecosystems have long relied on it alongside debuggers and SDKs to diagnose COM registration and interface contracts.

Overview

The tool surfaces runtime and registration data for COM classes, ActiveX controls, and type libraries used by applications like Microsoft Office, Internet Explorer, and Visual Studio. It displays information derived from Windows Registry entries maintained by services including Windows Installer, Component Services, and the Service Control Manager, and interoperates with development frameworks such as .NET, ATL, and MFC. Practitioners from firms like Apple, Oracle, and SAP often contrast COM inspection with platform-specific introspection tools from Google, Facebook, and Amazon when evaluating cross-platform integration or legacy interoperability.

Features

OLE/COM Object Viewer enumerates registered CLSIDs, IIDs, ProgIDs, type libraries, and monikers, exposing metadata analogous to that produced by tools such as Dependency Walker, Process Explorer, and Sysinternals utilities. It can query type libraries to reveal interfaces, methods, parameters, and GUIDs, similar in purpose to how tools including IDA Pro, WinDbg, and Visual Studio debugger reveal binary and debugging symbols. The viewer resolves registry keys created by installers from Microsoft, IBM, and Red Hat, and shows versioning and threading model attributes used by COM servers developed with technologies from Intel, ARM, or NVIDIA toolchains. Integration points with automation hosts like Microsoft Excel, Word, and PowerPoint are visible, allowing auditing of interfaces exposed by applications from Adobe, Corel, and Autodesk.

Usage

Developers launch the viewer from the Windows SDK, invoking commands to list registry-installed COM classes or to load type libraries, a workflow familiar to those using Visual Studio, Eclipse, or JetBrains IDEs. Typical tasks include diagnosing broken registrations after installation routines from InstallShield, WiX Toolset, or Advanced Installer, and validating GUIDs when building COM proxies with TLBEXP or MIDLC. System architects use the viewer to inspect monikers and running object tables when troubleshooting interprocess communication between services like SQL Server, IIS, and Exchange. Security analysts from Symantec, McAfee, and Kaspersky may use it to detect unexpected COM registrations installed by third-party software or by installers from Sony, Samsung, or LG.

Architecture and Components

At its core the viewer invokes COM runtime APIs implemented in components such as ole32.dll, oleaut32.dll, and proxy/stub libraries used by COM servers created with ATL or raw Win32 APIs. It interrogates the Windows Registry hive architecture including HKEY_CLASSES_ROOT and HKEY_LOCAL_MACHINE, and leverages the type library marshaling implemented in libraries maintained by Microsoft and contributors to projects like Wine and ReactOS. Internally it parses TypeLib binary formats produced by MIDL and compilers from vendors including Borland, GNU, and Microsoft, and it interacts with marshalling components used by distributed COM (DCOM) services commissioned by enterprises like Siemens, GE, and Philips. The viewer’s UI reflects shell integration patterns seen in tools such as ShellExView and registry editors from NirSoft.

History and Development

The utility evolved alongside Microsoft Windows and the Component Object Model, emerging during the 1990s as COM matured in products including Windows 95, Windows NT, and Windows 2000. Its development paralleled major Microsoft projects like Internet Explorer, Office, and the Windows SDK, and it became part of diagnostic suites distributed to partners such as Hewlett-Packard, Dell, and Lenovo. Over time the viewer remained relatively stable while complementary tooling advanced in Visual Studio, Windows Driver Kit, and Sysinternals, and open-source initiatives like Wine and ReactOS implemented analogous inspection capabilities informed by documentation from standards bodies and industry consortia such as the W3C and ECMA.

Alternatives and Related Tools

Several proprietary and open-source tools fulfill overlapping roles: Visual Studio’s Object Browser and Type Library Importer, Sysinternals’ utilities including Process Explorer and Autoruns, and third-party inspectors like Dependency Walker, IDA Pro, and PEiD. Cross-platform projects such as Wine and ReactOS provide COM analysis utilities usable by contributors from communities including GitHub, SourceForge, and Launchpad. Installer-focused solutions including InstallShield, WiX Toolset, and Advanced Installer offer complementary registration diagnostics, while static analysis and reverse-engineering suites from Hex-Rays, Synopsys, and Veracode address binary-level inspection needs.

Category:Microsoft development tools