I've been running into an intermittent problem that seems to be happening more frequently as of late. When I try to upload ppt files, I get the error shown in the attached image. The files are relatively small, under 10 MB. Sometimes I am successful the next day, but the latest occurrence has not resolved itself, so I'm completely stuck at the moment. I see the progress get to 99% uploaded, and then I get this error.
I tried again a short while ago, after first trying about two days ago, and this time the upload completed successfully. Hope this can get fixed soon.