While most spyware can be easily removed by programs such as SpyBot and Ad-Aware, some are resistant to these solutions and cannot be deleted in such a way. Spyware is a lot like a biological virus, it constantly mutates or changes to avoid being detected and deleted, which makes it very hard for designers of anti-spyware tools to keep up.

One such spyware program is "Coolwebsearch", which Ad-aware and SpyBot will detect and apparently delete, but the spyware will not be removed from your system.

The effects of Coolwebsearch are extremely annoying and intrusive, it hijacks your browser, - this is to say it takes you to a webpage you did not ask to go to, which can become extremely troublesome when trying to access pages such as bank account management. CWS will also take you to a spyware infested search engine if you forget to put the http:// in front of a web address.

CWS will also put icons on your desktop, mostly linking to pornography, it has also been known to install a toolbar for internet explorer which gets in the way and slows it down. One of the most irritating features of this spyware is that it significantly slows down your pc, and causes both system and program crashes, also random reboots - which can lead to loss of non-saved files.