Null Problemo! We have numerous tutorials on making a clean install covering every possible situation.
Supposedly the motherlode of these tutorials is:
Clean Reinstall - Factory OEM Windows 7
the approach is going to be to first wipe the disk clean and then perform the install.
CLEAN A HARD DISK PRIOR TO WINDOWS 7 INSTALL USING YOUR WINDOWS 7 DVD
TURN OFF THE COMPUTER WITH THE DVD TRAY OPEN Ø Turn on your computer.
Ø Open the DVD door.
Ø Turn off the computer with the DVD door open.
BOOT FROM YOUR WINDOWS 7 DVD AND GO TO A COMMAND PROMPT Ø Insert the Windows 7 DVD and close the DVD door.
Ø Power on your computer.
Ø When that very first dialog appears where you would normally push the NEXT button, then use the
SHIFT + F10 key combo to get to a command prompt.
Ø The command prompt will be
X:> USE THE DISKPART PROGRAM TO “CLEAN” THE HARD DISK
Type the commands shown, hitting the Enter key after each.
Do not proceed to the next command until the current command is finished.
· DISKPART (the command prompt will change to DISKPART>)
· LIST DISK (this will list the disks present)
· SELECT DISK 0 (assuming disk zero is the desired hard disk)
· DETAIL DISK (this will show you info regarding the disk you selected)
· CLEAN ALL (this is the command to write zeros to entire disk)
This can take half a day for a 2 Terabyte disk.
· EXIT(this will exit you from the DiskPart program)
· EXIT(this will exit you back to the Windows 7 install program)
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Now that your back in the Win 7 install program, you can continue with the install like normal. All signs and traces of everything is gone from your disk since each and every byte was overwritten with zeros.
That simple procedure is how I perform a clean install of Win 7.