OverviewCOM add-ins are an Office feature that was first implemented in Microsoft Office 2000. The architecture is supported by all Office programs, including Outlook. Key benefits of COM add-ins include:
- COM add-ins run in-process with the host program, so custom code generally runs faster than code implemented in Visual Basic for Applications.
- The basic COM add-in architecture is consistent across all Office programs, whereas in previous versions of Office, each program had its own add-in architecture.
- You can create one COM add-in to use with more than one Office program.
Important The COM add-in extensibility features were designed to run in-process with Outlook. Microsoft Customer Support Services cannot provide support for issues that are specific to COM add-ins that are written as out-of-process components.
What you need to create a COM add-inIn addition to Outlook, you need one of the following development environments to create a COM add-in for Office or Outlook:
- Visual Basic 5.0 or later (Visual Basic 6.0 is preferred)
- Microsoft Office Developer, which includes the ability to compile a Visual Basic for Applications project into a Dynamic Link Library (DLL)
- Any other COM-compliant development environment, such as Microsoft Visual C++ or Microsoft Visual J++
Resources and examplesThere are many resources and examples about how to implement an Office or Outlook COM add-in.
Outlook-specific informationCOM add-ins part I: Introducing an Office 2000 solution for the entire (Office) family:
General COM add-in informationMicrosoft Office 2000/Visual Basic Programmer's Guide
Chapter 11: Add-ins, Templates, Wizards, and Libraries: Microsoft Knowledge Base articles
Important things to know about OutlookThe following Microsoft Knowledge Base articles provide information about the key things that you should be aware of when you develop a COM add-in for Outlook:
Article ID: 291163 - Last Review: Jul 31, 2012 - Revision: 1