Hello Mac Community. I was just wondering if upgrading from Mac OS 9.0.4 to 9.1 (yes, old computer, i know, it's not mine) would erase any of the files. This is one of my Dad's computers at his office, so all of the files need to remain intact. The upgrade is the one that you can download from the Apple Support website and after you download it, it has two options: Install and Upgrade. I don't think it will erase any files, but I need to make sure. Thanks.