ok here we go -
start pc hit F12 select boot from disk
then select - start hirens boot cd
then select PARTITION TOOLS
then select FDISK
OK NOW YOU CAN SEE ALL THE SECTIONS OF YOUR HARD DRIVE YOU NEED TO DELETE THE PARTITION WITH THE ACTINE BOOT - ITS USUALLY AROUND 15 MB (USE F5 TO DELETE THE PARTITION)
when you restat the pc windows sees that there is no boot manager and you get the option to repair the computer and it builds a new boot sector( i then did a full scan with microsoft security essensials and malwarebytes as well as running kasperskys TDSSkiller tool and all come up clean.
One thing to try first - when your press f12 to boot from cd - in advanced boot options select - BOOT FROM HARD DRIVE - WINDOWS 7 (BOOTMGR) AND THIS SHOULD TAKE YOU TO YOUR DESK TOP.
THE ONLY PROBLEM I HAVE IS THAT AFTER NORMAL BOOT THERE IS A MESSAGE SAYING - YOU HARD DISK COULD BE INFECTED - YOU JUST HIT THE SPACE BAR AND IT BOOTS ( I WOULD NOT WORRY ABOUT THIS AS THE SYSTEM THINKS IT STILL MIGHT BE INFECTED - .
GOOD LUCK !!!!
HIRENS BOOT CD