I have a friend who has .odt documents in Mydocuments folder which suddenly appear without the extension but show the file type as "file". He can open these files with Openoffice, but cannot attach them, or print them. The also have a small icon at the left as a small rectangle with small red and bleu dots. If the text is highlighted and copied, then pasted into a new blank openoffice and saved as type openoffice, that new file also comes up with no extension, and displays as type "file" with the same problems - no attach or unprintable. I have never heard of this problem before!