Can you build a VSTO Excel solution in the latest Visual Studio on ARM?

Question

I see that there is now a native ARM version of Visual Studio which is great as i use Parallels Desktop on my mac and the previous version of Visual Studio is painfully slow. I see some workloads are available and some are not: https://developercommunity.visualstudio.com/search?space=8&q=%5BARM64%5D&stateGroup=active&ftype=idea&sort=relevance

One thing that is unclear to me is if it supports VSTO solutions. I know that the latest .Net framework versions don't support VSTO: https://github.com/dotnet/core/issues/5156 but I wasn't sure if there are any impediments of running the native ARM based version of Visual studio to run a VSTO solution on .Net 4.8 framework version.

Answer 1

No, it is not possible. Microsoft Office available for ARM-based processors doesn't support ARM-based COM add-ins (not emulated).

The Office apps utilize a new technology from Microsoft called ARM64EC, which stands for ARM64 Emulation Compatible. This technology allows developers to mix and match code that's built natively for ARM64 alongside code that runs in emulation. As a result, apps with dependencies that don't natively support ARM64 can run partly as native apps and partly in emulation.

Office has x64 code and legacy add-ins that aren't built for Windows 11 on ARM. With ARM64EC, Microsoft can rebuild large portions of the app to run natively on ARM devices, while the older components run in emulation.