I'm a Web Designer and when I open some PSD files in my Photoshop CS3 (Windows 7) I get these messages pop-up before to open PSD. My fellow designer use Photoshop on Mac OSX.
Some text layers contain fonts that are missing. These layers will need to have the missing fonts replaced before they can be used for vector based output.
Some groups were found corrupted and repaired.
This document contains unknown data which will be discarded to keep layers editable. To preserve the origional appearance instead, choose Flatten to load composite data as a flattened image.