Lately I've been trying to free up space in my 1 TB hard drive. I was down to only 1 GB, so I got this program called TreeSize. It helped me locate an exremely large video file that I didn't need. It was an 18 minute clip of a video game, sitting at 35 GB. Anyway, deleted that and in the file explorer my drive was showing about 34 GB free. A minute later, after looking some more at TreeSize to see what else I could delete, I looked at the drive again and it was 2.8 GB free. I had to delete another 20 GB file, and now it shows 23 GB free. Not sure what is going on but there's no way that space immediately got filled by something. Any advice?