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DO NOT install soft are like MacShop, Avast, Genio, etc.... these only add to the problem.
Use this the AdwareMedic tool to clean the AdwareMedic adware from your Mac. It has been tested and is the only software that ITS currently recommends for this task.
Click the DOWNLOAD link and run the software. This software is Donationware. The developer provides it for free. If you feel it is a valuable tool, please donate. It will identify the offending software, remove it and ask you to restart the computer. It is constantly being updated so if you need it again in the future, download a new copy.
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