The word document exists, the excel spreadsheet exists, and obviously knows it's supposed to be attached but word seems confused. any ideas?

This code works for me in both versions:

oDocument.MailMerge.OpenDataSource( lcExcelFile, ;
       0, 0, 0, 1, 0, "", "", 0, "", "", "Entire Spreadsheet", "", "", 0, 8 )

You may want to check out MSDN - this KB article may help:

Undocumented Expression for the OpenDataSource Method: SubType

PSS ID Number: 827891

Article Last Modified on 10/1/2003


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The information in this article applies to:


Microsoft Office Word 2003
Microsoft Visual Basic for Applications

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For a Microsoft Word 2002 version of this article, see 324378.

SUMMARY

Word 2003 includes an undocumented optional expression for the OpenDataSource method. This expression is named SubType.