"Harmful and malicous software detected. These programs may damage" is a result of rogue antispyware program Antivirus2009. Antivirus2009 infects user’s computer system and shows users misleading information about computer infection by showing fake scan reports, fake error messages like this one:

"Harmful and malicous software detected. These programs may damage your computer and steal your private information. Online Security scanner requires Antivirus 2009 components to repair your computer. Please click OK to download and install Antivirus 2009 components."

By showing this type of message Antivirus2009 wants to trick user in downloading this rogue antispyware program. And as usually Antivirus2009 will try to trick user that they need to buy its "full" version to "fix all of their problems. BUT Antivirus2009 won’t fix them because it is a rogue antispyware program by itself.
"Harmful and malicous software detected. These programs may damage" can also download other malware, Trojans or even viruses without user’s permission using browser security holes. WWW.Pcthreat.com recommends users to remove this dangerous adware from their computer system as soon as possible to prevent damage to their computer system!