I went to the QA Moodle and set up an upload a single file assignment. I then logged in as a student and uploaded a Word 2007 document - but when i tried to view it as the teacher it gave me that ? symbol which says that it doesn't recognise it-yet it was a simple Word 2007 document?
Interesting - Friday I get the unrecognised question mark - today I get the correct icon- and I didn't do anything different - never mind