VirtualDrive Pro is something similar to Alcohol 120 and DAEMON Tools. With its help you can add virtual drives, copy CD/DVD disks, emulate copy protections and so on.
Description: Play games and run CD/DVD applications without physical discs at 200X speed – plus, the build-in Virtual Hard Drive allows you to run games and applications up to 340 times faster in RAM! Now compatible with Windows 7! VirtualDrive Pro 12 CD emulator converts CDs and unprotected DVDs into compressed images, or “virtual discs,” which it plays in any one of up to 23 “virtual drives”. With VirtualDrive Pro 12, you’ll find a more responsive result, quieter playback, less wear and tear on a computer’s hardware, and complete freedom from physical discs, which can then be left at home, safe from theft or damage.

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