The is a set of components required to run Office add-ins and document-level customizations that were developed using Visual Studio 2010 (or earlier versions like VS 2008 with VSTO).
The 2010 version of the runtime introduced several critical improvements over older VBA (Visual Basic for Applications) technology: microsoft visual studio 2010 tools for office runtime
The Microsoft Visual Studio 2010 Tools for Office Runtime (VSTO 2010) is a set of development tools and runtime components that allows developers to create custom business solutions using Microsoft Office. It acts as a bridge between the .NET Framework and Microsoft Office applications, enabling the creation of application-level add-ins and document-level customizations. The is a set of components required to
The VSTO 2010 runtime offers several key features that make it an attractive choice for Office development: The VSTO 2010 runtime offers several key features
Uninstall any existing VSTO runtime, reboot, then install the official redistributable from the link above. Also ensure .NET Framework 3.5 or 4.x (depending on the add‑in) is installed.