My antivirus program might be blocking the Mixcraft installation

If you have an antivirus software which uses a "sandbox" or "Safe Zone", and you are having trouble getting Mixcraft to install, you may need to disable the antivirus program before installing, or add Mixcraft to the list of safe programs within the antivirus software.

Here's a video on  how to do that within Avast antivirus.

http://www.youtube.com/watch?v=4aGDhBqElXQ&feature=youtu.be