A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
I came across this trying to find a solution to the same problem and while it did not solve it, I eventually found the problem, so I thought I would share it for others who encounter it.
For reasons unknown, I had two files in my %APPDATA%\Microsoft\Excel\XLSTART folder--Personal.xlsb and Personal.xlsb.bak.
When I looked at the VBA Project in the VBA Editor, I could see that both were loaded--yes, it had loaded the ".bak" file, even though that is not an Excel extension. The two files were nearly identical, so the same functions were defined twice--once in the xlsb and once in the bak file.
This was causing the error blocking the recording of the new macro--the error was not really related to the new macro; rather, it was complaining about the existing situation.
I closed Excel, removed the ".bak" file, restarted, and everything worked fine after that.
So, if you encounter the error that you cannot record a new macro, look for any existing duplicate function definitions and clean those up and your problem should hopefully go away!