Trojans, spyware and other malicious programs that make their way into your PC system uninvited, typically have very bad intentions and create serious problems for the user. In many cases these malware programs only cause disruption, in many other cases they create an opportunity for serious criminal activity such as identity theft.

Trojans and spyware programs can also infect a PC with the intention of joining that PC to a "Botnet", these are networks of other infected PCs that are controlled by a main server run by a hacker who issues commands to these zombie PCs to act as one in an effort to carry out activities such as DOS attacks, and spam.

How do you find these malicious programs and more importantly how to do you get rid of them? It is absulutely critical that any PC user who takes part in any online activity take the proactive measure of employing an Antivirus and Anti Spyware program to provide a good protection front for their PC. If you're not running either one of these programs but suspect that there's something wrong with your system, here are some of the most common places trojan horses and other malicious programs hide:

• Users Start Menu - look for any program folders that you do not recognize or did not mean to install.
• %windir%\systenm32\AUTOEXEC.NT - open the file and look for any paths to startup files for programs you do not recognize.
• HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run
• HKLM\Software\Microsoft\Windows\CurrentVersion\Run
• HKLM\Software\Microsoft\Windows\CurrentVersion\RunOnce
• HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices
• HKLM\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce
• HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run
• HKCU\Software\Microsoft\Windows\CurrentVersion\Run
• HKCU\Software\Microsoft\Windows\CurrentVersion\RunOnce
• HKCU\Software\Microsoft\Windows\CurrentVersion\RunServices
• HKCU\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce
• HKCU\Software\Microsoft\Windows NT\CurrentVersion\Windows\run
• HKCU\Software\Microsoft\Windows NT\CurrentVersion\Windows\load
• HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Run
• HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer\Run
• HKEY_USERS\.DEFAULT\Software\Microsoft\Windows NT\CurrentVersion\Windows\load
• HKEY_USERS\.DEFAULT\Software\Microsoft\Windows NT\CurrentVersion\Windows\run

If you do find suspicious file names or programs hidden in odd locations, there's a very good chance you have been infected.

A few solutions - First and foremost if you are not running an antivirus and anti spyware programs you must download them and install them immediately, when the programs run an initial scan of your system they may or may not find the infected files, in which case you may need a cleaner to get rid of all infections.

Antivirus and anti spyware programs are better at prevention than actually cleaning up a mess after it's already happened, so search the Mcaffe and Symantec sites for cleaners that may help you get rid of the trojan horse or other infection. It would be best to allow the AV and AS to run first though.

Lastly, when you do register your protection programs make sure they're kept up to date, and if feasible for you also install a firewall which will add an additional layer of protection. For a great all-in-one protection suite, check out Kapersky Internet Security.