You've got to do a clean install of Windows 7. That works on a clean (empty) hard disk. So just do it on a new hard disk (using the old one as a backiup) or buy a new hard disk as backup for your lots of personal files, before you clen the old one. Your choice how to use the old and the new disk. Having a separate disk for backup, of course, is a necessity.
Are you aware that the Dell OEM license only is valid on the original Dell hardware, and now is void? So you need a new license for your new OS in your new PC.
Kees
I have a dead Dell PC, the HD is OK, I used an external USB adapter to test it and see all of the files. I want to build a cheap standard PC and would like to use the old HD and OS.. but it doesn't boot, keeps going back the the safe start screen. I even tried to install a new Win 7 OS but it says the HD files are a different type so it can't do that either. I would like to use the old HD because lots of personal files etc. are on it, but I can't even do the new install. I know I could back it all up via the USB HD adapter... any magic tricks I can use???

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