There are a number of indicators you can watch for which will suggest that your computer has been infected by spyware or adware. Please note that some of the symptoms listed below are not unique to just a spyware or an adware infection.

1) PC Performance – Both Spyware and adware consume your PC's resource like computer memory. A bad spyware infection could dramatically slow your computer's performance including causing your system's to become increasingly unstable. Spyware also can affect your internet connection speed as it takes up bandwidth to communicate information back to its creator.

2) Pop up Ads – It is highly likely that your computer is infected by Adware if you notice more pop up ads appearing than usual. In some cases pop ads start appearing on the desktop even if you have not opened a web browser. Alternatively, search results may appear in a pop up or another browser window relative to the website you are visiting or keyword term you have typed into a search engine.

3) Browser Toolbars – These programs are commonly bundled with free software which the publisher often describes as "advertiser supported." The toolbar then feeds adverts based on the website you visit. They are usually very difficult to uninstall. "180 Search Assistant" and "Huntbar" are example programs.

4) Browser Settings – Your internet favourites or bookmarks and start page are two main settings which are targeted by spyware authors. Web sites are inserted into your list of internet favourites in the hope that you will visit them. Browser hijackers change the start page which is visited when the browser loads. Any unexpected change to your start page is a sign of infection.

5) Start Up Programs – Some spyware variants will try to add themselves to your Windows start up program list. If you boot up time becomes noticeably slower then review your program start up list to check for applications you are not familiar with and remove them. This program list can be review using the "MS Config" option from the Windows XP Run command.

6) Software Failure – A spyware infection can cause some of your programs to crash or stop working. In particular watch if your Internet Explorer browser refuses to work all of a sudden.

7) Hosts File Changes – The Hosts File is a Windows file that maps the numerical IP Address to the Host Name very much like the address book on your cell phone "maps" your friend's name to their telephone number. Some spyware programs can change these setting so that when you type in "www.cokoye.com" for example you are re-directed the spyware author's website.