how to delete defence center virus?

HI ,First of all try to start task manager (press ctrl+shift+esc) right after logging in and stop these processes:defcnt.exe spam001.exe spam003.exe troj000.exe. Also, you must stop everything that should not be there, more I found in this guide : http://www.2-spyware.com/remove-defense-Then download and scan your PC with a reputable anti-spyware, Spyware Doctor, Malwarebytes or SuperAntispyware.You can also check how to remove Defense Center (Removal Guide)
http://www.bleepingcomputer.com/virus-re. You can also try removing the virus in safe mode since the virus will probably not load in safe mode.I am sure that this will work for you and you will be able to delete defence center virus. Try above mentioned methods and get rid of it.