VFP6 SP5, Excel 97

Let's say I create a new Excel document. I don't put anything fancy in it, just "Test" in the first cell. I save this document as "D:\Test.XLS".

Now, in VFP, I do this:

CREATE CURSOR Test (Test G)
APPEND BLANK
APPEND GENERAL Test FROM "d:\Test.XLS"

The Append General command bombs with "OLE error code 0x80070001: Incorrect function" (the description may not be exact, I have a French Canadian Excel, so what I really have is "Fonction incorrecte").

Doing something similar in Word works like a charm. Excel used to work before, and as far as I can tell it has not changed since then. This behavior occurs both on a "client" machine and on my development machine. Both are WinNT4. I just tried on the 2 laptops and it works fine. One is Win98, the other is Win2000. I also tried on another NT4 workstation and it works fine too.

Yes, I did try rebooting! :)

Any ideas?