Thanks for getting back to me. I just looked in autosave. The file that won't open was last saved at 11:02pm on the 16th. There was an autosave project at 10.25pm on the 16th, and that wouldn't open either (it crashes at exactly the same place as the other one). However, there was an autosave file at 6:17pm on the 16th that would open. Curious though, it doesn't seem to have a lot of the changes I thought I had made by this time. It seems to be earlier than this (although perhaps my memory isn't serving me correctly). Should there be more autosaves that this? I had the program open pretty much that whole time, and nothing between 6:17 and 10:25.
Anyway, that's a start! Something must have happened between 6.17pm and 10.25pm that'd made the file go kaput. I would love to know what, so I can avoid this happening again. First things first though, it'd be fantastic to get the file that isn't opening working.
Thanks for your swift response too, Jim. I opened PP and tried to open the file from the interface. The load project bar stopped at the same place. I can open other projects fine. As to your last suggestion, I created a new project, and went to File/Import then clicked on the file in question. It started importing, then the progress bar froze at exactly the same place. I'm not sure if I did this correctly. Is there another way to import a PP file into an existing PP?
Thanks again for your time. It's just nice to speak to someone about this because I really freaked out when it happened.