Getting error of duplicate function but there is only one function with that name

I am getting an error that a function already exists, but if I remove/comment out that function, it shows that error because that function no longer exists.

So weird!! never faced this problem until Igor 9!!!!

error when trying to compile with the function ON When that Function is commented out!!!

Hmm... that seems indeed strange. Can you reduce your code to the minimal possible example where this happens and then post a self-contained experiment file here? I (seldomly) have weird compile issues which go away after restarting Igor, but I assume you tried this already?