Tried this again today on my work computer, after a reboot, and still no joy. Rebuilt the graph from scratch in Revit 2021 (Dynamo 2.6.1) and still got the same error. Excel opens, but it does not go to the referenced sheet or read any data.
Tried again tonight on my home computer, Revit 2022/Dynamo 2.10.1. Have not got around to setting up any packages on this version, but all of the nodes I was using were from Dynamo, so that was not an issue. Works fine at home. Slightly different version of Excel - Microsoft Office Professional Plus 2016, Version 2016 (Build 14131.20320). Looks like there are updates to install, but no time for that tonight.
So “we” must have done something at work that is breaking the Data.ImportExcel node’s ability to read data out of Excel. I have noticed that my old Excel Macro file (Personal.xlsb) that used to open every time I started Excel no longer opens, and I thought I saw some warning message stating that my company had disabled Excel macros. Perhaps that is the cause. I will have to enquire about that on Monday.
David