“System is vulnerable to attacks.” is a popup window coming from a rogue program TrustNinja. The full message reads:
System is vulnerable to attacks.
Attention: DANGER!
TrustNinja detected that This PC NOT PROTECTED. Currently installed malware application cause:

Have an error messages like “This application has failed to start because the application configuration is incorrect…” can be cause by a rogue program infection. FakeAlert-GA or Windows Antivirus Pro is the culprit for this error. The full messages reads:

“Total Security Firewall Alert” is part of Total Security rogue program operation to mislead computer users to download and install the program. The message states that:

“Security Monitor: Warning!” is a popup message initiated by a rogue program Total Security. The full message read:
Security Monitor: Warning!
Attention! System detected a potential hazard (Trojan SPM/LX) on your computer that may infect executable files. Your private information and PC safety is at risk. To get rid of unwanted spyware and keep your computer safe [...]

AntiAdware System Scanner carries the slogan of “Online protection against malicious software.”In reality, AntiAdware System Scanner is a window that is the start of computer users problem. Once this is executed, more annoyances such as additional malware and fake alerts will continue to popup and promote different kinds of rogue programs.

“Hardware and security errors detected” is part of a fake “Windows Explorer” that will perform security scanning on computer automatically without users intervention. This activity is related to promotion of rogue programs. The message may appear like:
Hardware and security errors detected
Hardware errors
Performance of your PC is low due to a file system error. It was [...]

“Harmful and malicious software detected” is a fake virus scan result that will pop-up on computers who are already compromised with a fake antivirus. This warning messages will lead to downloading of another threats and has a full message of…
WARNING!
Harmful and malicious software detected
Online Scanner detected programs that may compromise your privacy or damage your [...]

“Warning! Spyware is part of an overall public concern about privacy!” is identified to be part of a certain rogue antivirus program and was produced to get computer users attention on security issue. The window will pretend to be an online scanner with messages:
Warning! Spyware is part of an overall public concern about privacy!
Adult screenshot [...]

“Warning! Windows has been infected” popup message was found to be a part of a rogue security program operations on the infected computer to promote itself. Once user was convinced with these tactics and start to download a program. Expect that other malware will be downloaded onto the computer to perform different annoyances. This warning [...]

“Warning! Detected porn files” is a popup warning message on computer that was compromised with a rogue anti-spyware application. These are misleading alerts that may lead to downloading of another malware. The full message reads:
Warning!!! Detected porn files
Hard drive scanner results: Warning! Your computer is full of porn files