My computer appears to have come down with something nasty. The program started by hijacking Microsoft Security Essentials, claiming that a Trojan was on the computer and that a download of "Windows Defender Online" was necessary for complete removal. A search on google suggested this program was legitimate, but upon doing the download, the "Internet Security 2014" installed itself, and has been claiming false instances of malicious software (ex. "blaster worm"). This program refuses to allow any other .exe files to open, claiming that they are malicious and have been stopped. The program also demands I need to "activate" it in order to "cure my computer."
Upon the infection of MSE, I ran Malwarebytes, ESETscan, and TDSSKiller; none detected anything. The svchost.exe program was repeatedly launching and usually an abnormally large amount of space. as much as 1000000 kb. Seeing as I have been unable to remove this malware on my own, I could use some guidance so that I can return my computer to a working, uninfected state.
Thank you, I appreciate any and all help.