Buddy... re-installing Windows is not enough... when you re-install Windows, viruses and junk files remain in the PC because you only format Drive C:... what about other driver..? you should clean junk files from the other drives also...!!
When i re-installed a clean version of Windows, I completely reformatted the hard drive, there is NO secondary hard drive, all the old files are completely deleted. This is a clean version of Windows on a clean hard drive.