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DO NOT install software such as MacShop, Avast, Genio, etc.... these only add to the problem.
Use Malwarebytes for Mac tool to clean the adware from your Mac. It has been tested and is the only software that ITS currently recommends for this task.
https://www.malwarebytes.com/antimalware/mac/
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.
The SafeMac web site also has some good information about the need for Anti-virus software, Macs & Malware and increasing mac performance. Check it out...
While Adware usually will not harm your computer or delete your files and Macs are protected relatively well by Apple's built in tools (called XProtect) some users prefer to have anti-virus software installed. ITS strangle recommends against packages such as Norton, Symantec, Macafee and Sophos. While to do a good job, they also severely affect system performance. If you feel that you need anti-virus software, consider using ClamXAV, which offer personal license for a fee. It does not run active processes that hinder the computers performance but does run updates and scans on a regular schedule.
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