Quote Originally Posted by Karen View Post
You, the sender, should always "save down" to be compatible with older versions, it's the polite thing to do, unless you are sure of the receiver's capabilities.
Just remember that some functions (noteably, Excel calculation scripts) often do not 'save down' correctly. Be sure to let the recipient of the 'down' version know that, if its a Excel sheet with calculations.... Or a Power Point file with Flash content embedded.... or a Access database.... Or if you intend to use any content with a SharePoint site.