Very often spyware can crash even the most powerful computer and can make your programs behave in a mad manner. Many anti-virus programs are not of great help against adware and spyware simply because they are intended to fight viruses only and as a result they neither can catch, nor remove adware and malware. However, some of the best antivirus programs from vendors like McAfee or Norton, do include modules against adware and spyware, so if you get such a program, you will be protected against adware and spyware as well.

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