The mojopac and ringcube does not require a fresh install. Since it's partly virtualizing the operating system, not the software thus a fresh install is not needed.
You'll have to install the software on top of the virtualized "mojopac" or "ringcube" virtualize OS.
Mojopac and ringcube both have trials. I would've test it out for you guys, but my computer is very slow. It's almost 7 years old. Running the software on windows xp is already slow enough.
Too mojopac doesn't run on windows vista. I'm not sure if ringcube runs on windows vista or not, but I think it won't. Both software are based on the same technology and made by the same company.
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