Can't. None of the Revit releases are backwards compatible. You might try
exporting it to a an IFC file and seeing if they open that. I am not sure
what information will be missing or how useable the file will be. It sounds
like they need to upgrade to 2008.
wrote in message news:5666587@discussion.autodesk.com...
I have a database I created in 2008 I need someone to read in the pervious
version 9.1. how do I save down my file.