Any clues how to do programmatically copy data from an Excel file that
is being viewed in IE?

Background: I'm using Excel VBA and the internetexplorer.application
object to programmatically retrieve a URL that is actually an Excel
file, e.g.:

Set ie = CreateObject("internetexplorer.application")
ie.navigate "http://whatever.com/?format=EXCEL"

My goal is to copy this data into another Excel file. The problem is
that even though this Excel file opens in IE, I can't copy the data
using ie.document.execCommand "SelectAll" and .execCommand "copy". I
also tried copying the data using the ActiveWorkbook object, but this
doesn't work either--ActiveWorkbook apparently only picks up workbooks
that are not open in IE.

Thanks,

David