In the past I have spent some time with the Office Automation APIs and with the recent release of Office 2010, it seems as good as any time to open up Pandora’s Box and try again.
I have bundled up some basic functions for converting Word, Excel and PowerPoint documents to the previous version; you can find them here at http://www.commandbreak.com/content/binary/convert_Officefiles.zip. Not much has changed and these functions all utilise the Application.Open and Application.SaveAs methods.
Enjoy