It won’t overwrite but it expects a folder in it named XY4, and won’t work without it. So RENAME your existing DOSBoxDisk and try out the new system first. This is ABSOLUTELY crucial. Then, if you like the new system, you can bring in stuff from the old disk. If you don’t like it, just delete it and restore your old renamed disk. --Mistyped from a phone. Please forgive typos and brevity.