Loading .NET Framework - Soooooo?

[Martin Noyes]

When I launch an Excel workbook in Microsoft 365 I get a Launching .NET Framework message at the bottom. What does that do for me? Can I connect to a server using html/TCP on my LAN? If so, how? I've tried using Visual Studio 2019 to build a network Excel AddIn but VS security would never let it execute the Web Socket.

[#2]

It is likely that the workbook in question contains queries from the Data, Get and Transform section, also known as PowerQuery. PowerQuery uses the .NET framework, hence it loads when you open a workbook which contains (or has contained) any PQ connections.

[#3]

@Jan Karel Pieterse 

I have the same problem. In any .xlsx file, just open PowerQuery editor, save and close it. From that moment, every time you open that xlsx file, "loading .Net Framework" label will appear, no matter what you do...