Client Access Download To Excel - Excel Format?

We have some files that are downloaded from out iSeries using Client
Access (actually using RTOPCB) onto a network folder.
In another Excel workbook we need to import the data from these
(Data / Import in Excel).

This works fine for some of the downloaded spreadsheets, Excel brings
up the Select Table and then Import data windows, but for some of the
other files it brings up Data Link Properties and thinks I am trying
to link to an Access Database.

I have no idea why this is happening, all of the files have been
created in the same way using RTOPCB.

Now if I open one of the files that I have problems with and Save it
in Excel, I can import it ok, so I think it might have something to do
with the version of Excel that the file is being crearted as (BIF8 in
RTOPCB).

I'm hoping someone out there might know the answer or what I can do to
eliminate these problems.

Note: this is being posted to both AS400 and Excel groups.

Thanks in advance.