Batch convert files to Office 2007 format

[Andy Siegel]

Is there a way to convert Office 2003 files to the newer Office 2007 format
without having to open each file and saving in the new format?

The individual method increases disk utilization by 50% because you still
have the original .doc and a newer .docx file that is half the size. Is
there a more efficient method to do this? I have a large file server and
this could take months to get them all converted.

Thanks,
Andy Siegel