There are two answers to that question, actually three!
How to prevent ads and pop-ups: Download and install GlimmerBlocker: http://glimmerblocker.org/ Configuration file for app on mac.
CleanMyMac X has thousands hours of work behind it and this is the hours you save using it. For example, Smart Scan does 3 jobs in one click: it cleans, protects, and brings your Mac up to speed. If your Mac is underperforming, give CleanMyMac X a spin. You will wonder how you ever got along without it. IServices Trojan Removal Tool is a free tool to remove the iServices Trojan horse spyware. IServices Trojan Removal Tool is a free utility created to remove the iServices Trojan horse from infected Mac computers running Mac OS X.
How to prevent re-direction:
![Removal Removal](/uploads/1/3/4/1/134170371/962776731.jpg)
Adding Open DNS codes to your Network Preferences, should give good results in terms of speed-up as well as added security, (including anti-phishing and redirects) (Full information about Open DNS is here: http://www.opendns.com/home/nobloat ) and further independent information can be read here:
and here:
Open System Preferences/Network. Double click on your connection type, or select it in the drop-down menu, and in the box marked 'DNS Servers' add the following two numbers:
208.67.220.220
(You can also enter them if you click on Advanced and then DNS)
Thirdly: malware!
There are many forms of ‘Malware’ that can affect a computer system, of which ‘a virus’ is but one type, ‘trojans’ another. Using the strict definition of a computer virus, no viruses that can attack OS X have so far been detected 'in the wild', i.e. in anything other than laboratory conditions. The same is not true of other forms of malware, such as Trojans. Whilst it is a fairly safe bet that your Mac will NOT be infected by a virus, it may have other security-related problem, but more likely a technical problem unrelated to any malware threat.
You may find this User Tip on Viruses, Trojan Detection and Removal, as well as general Internet Security and Privacy, useful:
Free App Removal For Mac 10.6.8 Free Download
The User Tip (which you are welcome to print out and retain for future reference) seeks to offer guidance on the main security threats and how to avoid them.