Something that hasn't been mentioned yet, is that having the autogrow set to 10% isn't usually the best practice and this could be causing the out of space error because a 28GB file is trying to grow another 2.8GB on a drive that is smaller than the required 30.8 GB. In addition to all the other recommendations, I'd recommend setting the data file to the size of the drive, not allow autogrowth, and monitor space available (% used) and have an alert setup that lets you know when you are running out of space.