Safari open new tabs with ads on every click

I assume you have adware. Follow the instructions on this web page in order to manually remove adware from your mac: https://support.apple.com/en-us/HT203987

You may also find adware removal guide on this page http://www.thesafemac.com/arg-identification/

If you do not want to remove adware manually use adware medic tool in order to scan and remove it: http://www.adwaremedic.com/

Download, open adwaremedic dmg file , and run it by clicking “Scan for Adware” button to remove adware.

Once done, quit AdwareMedic and restart your mac.

Install adblock for your browser: https://adblockplus.org/

ionast wrote:

As a final solution I clean installed OSX 10.8 (Mountain Lion) yesterday and with great surprise the ads are back again today.

When you say you "clean installed" it, what do you mean? A true "clean" reinstall would involve erasing the hard drive, then reinstalling the system onto this empty hard drive. Typically, when testing a problem by using a clean reinstall, you would test the problem before adding any third-party apps. A clean reinstall also does not involve migrating apps, user data and settings using Migration Assistant. Is this what you did? If so, and you're still having ad problems on that clean system, you probably have a problem other than adware... perhaps hacked network hardware:

http://www.adwaremedic.com/kb/hackedrouter.php

(Fair disclosure: I may receive compensation from links to my sites, TheSafeMac.com and AdwareMedic.com.)

If you just reinstalled on top of your current system without erasing first, or if you used Migration Assistant (or something similar) to import apps and whatnot, then that was not a clean reinstall, and would not have solved a problem due to adware. See thunderzzz's post for details on how to solve an adware problem.

No problem, glad to be of assistance!