How are you opening Excel? If it's from a shortcut, you may need to create a
new one. Was Excel re-installed after the HD was added?
Will Excel files open if clicked directly? That is, find an Excel file,
click it before opening Excel. You may need to clear the recent documents
list. Doc files are usually Word files, of course, and Excel can't open
them.
I'm not sure if "enmessed" is a word, but if it isn't it should be.
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Not sure if this is the right list for this question but the problem started
with the installation of a new hard drive.  I had it partitioned into 2
sections, D and E, and everything seemed fine.

But when I open Excel 2000, before the programme has time to finish loading,
I get a Microsoft Excel warning box saying <<the ****.doc file format is not
valid>>.  When I click OK, the next file on the D drive appears with the
same message, and I have to go through every file on the D drive before it
will let me open an excel file.  This happens even when the Excel file I'm
trying to open is held on the C drive.  (In other words, Excel has somehow
become enmessed with the D drive.)

What I'm wondering is, does anyone out there know if this is a hard drive
setting problem or an Excel problem - no point reinstalling Excel if its the
hard drive.

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