Unable to reformat!

[Callme]

Hi,

can anyone help me with this? I posted a problem earlier, and decided to try reformating my pc. Problem is that I cant repair coz I do not know the password. so I want to delete the old operating system n install a new one. I was unable to do that as I got a msg telling me that the system contains setup files that are required to complete the installation. Anyone can help me with this? Thanks in advance.