The Visual Studio Tools for Office (VSTO) runtime is considered a mature but still maintained technology. The VSTO runtime is supported and serviced as long as it is running on a supported version of Office. The last major version update was .NET Framework 4.8, and Microsoft has announced that there will be no .NET 5+ or .NET Core version due to technical limitations with in-process loading. While it is not a platform for new, large-scale development, it is fully supported for maintaining and running existing solutions. Microsoft's official recommendation for new projects is to use the modern, web-based Office Add-ins model.
: Before installation, you must have the .NET Framework 3.5, 4.0, or newer installed on the machine.
: A set of unmanaged DLLs that load the runtime and the specific solution.
The runtime package consists of several core components that manage the security and execution of Office extensions: The VSTO Loader microsoft visual studio 2010 tools for office runtime -x64-
If an Office add-in stops working, the VSTO Runtime is often the first place to check. Add-in "Not Loaded" Error
Go to Control Panel → Programs and Features . Look for "Microsoft Visual Studio 2010 Tools for Office Runtime (x64)" . Uninstall. Then manually delete %ProgramFiles%\Microsoft Visual Studio 10.0\VSTO Runtime and clean the registry keys mentioned earlier.
Re-running the installer and selecting the Repair option typically restores missing registry keys under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VSTO Runtime Setup\v4 . Security and Trust Models The Visual Studio Tools for Office (VSTO) runtime
It is possible to see both x86 and x64 entries for the VSTO runtime in your installed programs list. In many cases, this is by design and is not a problem. For instance, a 64-bit version of Windows will often have both runtimes installed to support a wider range of older and newer solutions.
Yes, but it is not recommended. The x64 installer places files in Program Files and 64-bit registry; the x86 installer uses Program Files (x86) and the WOW6432Node registry. However, if you have both, Windows will attempt to load the appropriate version based on the calling process (Office x86 uses x86 runtime; Office x64 uses x64 runtime). This works in theory, but causes clutter and occasional loader conflicts.
"The managed add-in [YourAddIn] was loaded successfully into the host process EXCEL.EXE (64-bit)." While it is not a platform for new,
The is an essential, if specialized, component for the Office ecosystem. It enables the powerful and feature-rich add-ins that extend the functionality of 64-bit Microsoft Office applications. While its age presents some installation challenges, it remains a stable and well-supported technology for running and maintaining existing Office solutions. For developers and IT administrators managing 64-bit Office environments, understanding how to correctly deploy and troubleshoot this runtime is a key to ensuring those critical business add-ins continue to function reliably.
Are you looking to with the runtime, or are you deploying a new add-in for users? Visual Studio 2010 Tools for Office Runtime - Microsoft
Third-party software (like SAP or Oracle) that exports data directly into formatted Excel sheets or utilizes Word templates.
A simple but common issue is a stalled or background Windows Installer process. If you get a message that another installation is in progress, a reboot of the computer will often clear the stuck installer and allow the VSTO runtime installation to proceed.