How to install Microsoft.Office.Interop.Excel.dll for Dynamo via Revit2021? Office2007?

[Marcel_Rijsmus]

Import info from Excel? Data.ImportExcel operation Failed

I had the same issue, import excel failed. I realized that recently IT had a rough time installing MS Project, and probably had to reinstall Office, but likely did 32-bit. I had to uninstall MS 365 Apps AND MS Project separately before I could install 64-bit apps from my MS account from Office.com. I didn’t need to restart or press special OK accept terms type thing, I just fired up Civil 3D and Dynamo and the node now works.

Hope it helps