Several students are working on an 8th grade banquet PowerPoint presentation, have been saving regularly on hard drive, but no backups on the zip drive since MANY hrs of work ago. After last save, we cannot open the presentation. It seems to try, but gets about 4 bars into the opening, and we get the message "PowerPoint can't open the type of file represented by 8th grade video.ppt". File type is right. Have copied it to a notebook computer using direct cable connect but we get the same thing. Have tried renaming it, but no luck. Have tried copying it (it seems to copy okay) but will not open, either the original or any of the copies. Could it be that the file is too big (it's 42 megs)? Is there any hope of retrieving the file? Help??!!!! Thanks.