C:\Program Files\Autodesk\Inventor [Version]\Bin\Public Assemblies\Autodesk.Inventor.Interop.dll
No, you generally do not need to recompile for every minor build or service pack. However, it is strongly recommended to recompile for each major new version of Inventor (e.g., moving from Inventor 2024 to Inventor 2025). Autodesk's support for the Interop DLL typically extends back two major versions, meaning your add-in will likely continue to function across three releases before an update is required.
Have you run into strange interop issues with Inventor? Share your experience in the comments below.
If you are developing custom software, add-ins, or automation scripts for Autodesk Inventor, you will inevitably encounter . This dynamic-link library (DLL) serves as the essential translation bridge between the Microsoft .NET framework and Autodesk Inventor's underlying COM (Component Object Model) architecture. autodesk.inventor.interop.dll
Autodesk Inventor is natively built using C++ and exposes its features to the outside world via COM interfaces. Modern Windows development, however, heavily relies on .NET languages like C# and VB.NET. Because .NET cannot communicate with COM directly, it requires an intermediary layer.
Manually release your COM objects when your program finishes using Marshal.ReleaseComObject(inventorApp); . Best Practices for Enterprise Automation
To prepare content for or use the Autodesk.Inventor.Interop.dll Have you run into strange interop issues with Inventor
When an Inventor version is installed, its specific Autodesk.Inventor.Interop.dll is added to the GAC. This results in a single folder ( C:\Windows\Microsoft.NET\assembly\GAC_MSIL\Autodesk.Inventor.Interop ) containing numerous versioned subfolders (e.g., v4.0_17.0.0.0... , v4.0_26.0.0.0... ). This allows multiple versions to coexist without conflict.
Developers frequently encounter versioning and environment conflicts. Below are the consensus "best practices" from the Autodesk Community and technical support: Different version of Autodesk.Inventor.Interop.dll
// C# Example: Creating a new Part PartDocument oPartDoc = (PartDocument)invApp.Documents.Add(DocumentTypeEnum.kPartDocumentObject); Use code with caution. Best Practices and Tips This dynamic-link library (DLL) serves as the essential
: Referencing this DLL provides access to the Inventor namespace, which includes classes for parts, assemblies, drawings, and iLogic. Standard File Locations
When developing an add-in, you usually reference this DLL from the installed directory. When distributing your application, you generally rely on the user having Inventor installed, or you include the specific redistribution policy defined by Autodesk.