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How to reinstall windows 7 if I have win7 x32 installed and I want to replace it with win7 x64?(I don't want to format my hard drive)

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marked as duplicate by and31415, Excellll, Garrett, James, digitxp Jul 23 at 17:26

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If you don’t want to format, your data is probably on the operating system partition. Now would be a good time to change that. –  Daniel B Jul 22 at 6:18

2 Answers 2

Please refer to Microsoft's Windows 7 install and upgrade FAQs for your information.

You cannot upgrade architectures without performing a "clean" install of Windows. This is due to most of the 32-Bit and 64-Bit system files being incompatible across versions.

Ref: http://windows.microsoft.com/en-gb/windows/32-bit-and-64-bit-windows

What you are trying to do will not work unless you do the following:

  1. Partition your existing hard disk so you can dual-boot one or the other versions - thus keeping your personal files on one partition which you could migrate to your 64-Bit partition and then extend the partition to cover your whole disk. You will need to make sure you have enough space to fit the second OS + duplicate your data files.

  2. The same as above but install Win 7 64-Bit on a second hard disk as a dual-boot.

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  1. First you want to make sure that you're DVD drive is selected as the first boot device in your BIOS.
  2. Boot from your Win 7 DVD.
  3. Once loaded, select install.
  4. After its extracted the initial setup files, you'll be given a screen showing all your drives.
  5. Select the current drive that Windows is installed on.
  6. It should prompt you saying that it will install a new version of Windows and create an "Old Windows" folder; containing your old installation of Windows.
  7. Continue with the install and once its finished, if you so chose, you can delete the "Old Windows" folder once you've booted back into your new version of Windows.

Can I ask though, why don't you want to format your drive?

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Also to add that you cannot "upgrade" architectures without formatting. A change in OS architecture (32-Bit to 64-Bit and vice versa) requires a clean install. A possible solution would be to dual-boot. This will require the OP to partition their disk to fit both OSes on. –  Big Chris Jul 22 at 6:27
    
@BigChris Sure you can. You don’t have to format you drive to reinstall Windows, but it’ll be a real mess afterwards. –  Daniel B Jul 22 at 12:06

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