I have a computer, two new harddrives. I have a Windows 7 Home Premium COA and I am trying to load on this computer. I have 4 discs, three with ISO versions of Win 7 Home Prem and one from the manufacturer. Each version gets hung up and stops at Expanding Windows files and will go no further. As a lark I attempted to load Windows 7 Professional using a default product key, it loaded without issues. I removed all but one memory stick. Help me, please.