Moved to Il-2 Technical Help.
Planemad
Easy. Simply copy your installation folder to a different location. Il-2 runs without registry entries, thus you can have lots of copies of Il-2 on your machine.
Like Bearkiller said, copy the files over.
I have 3 copies,
4.09M UP 2.01
4.101
4.10M Modded
Planemad
Relax, relax! Just make a copy of your existing installation (you did already, as I understand), then uninstall the old installation and install again from DVD.
That way, you should have your old installation folder/game folder moved aside safely and still can play your HSFX version.
That's it. And while you're at it, also make a backup of the newly installed Il-2 4.07m and store that one for future testing/tweaking/backup. :wink: