32 bit to 64 bit

I purchased Windows 7 Home Premium as part of a supplied computer system approx. 2 years ago.
The OS package contained two disks, one to install W7 32 bit & the other W7 64 bit. I installed the 32 bit OS but now are considering installing the 64 bit OS. Is it permissable to uninstall the 32 bit system & install the 64 bit in its place or must I purchase another W7 OS? It appears there is only one product key for both.

I attempted to contact Microsoft by email but, after this length of time, the activation number I was requested to submit had apparently expired.


Windows Forum Admin
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For so long as you received the software as part of one bundle for a single computer system, you should be able to perform a clean install and properly license this system for the 64 bit version. The issue of licensing will come up during Windows Genuine Activation (WGA). You will want to enter the activation key that was supplied to you by Microsoft. You will have a grace period to activate the OS. Please bear in mind that whether or not you have a OEM or RETAIL license may be inconsequential during actual activation: The success of this process is dependant on how many times you have already performed the operation, as well as a number of other factors. Should online activation fail, you will be prompted to call Microsoft's regional hotline to perform automated telephone activation. In short, it is very much possible to use the same license key for Windows 7 64 bit, for so long as this is what was supplied to you as part of the software bundle. Copies of Windows 7 typically contain both 64 bit and 32 bit while one license still applies. You will want to prepare for a completely clean install prior to your migration. You should back up and copy critical files in order to access them on your new installation. As you likely already know, it is not possible to perform any kind of upgrade from 32 bit to 64 bit at this time.

Good luck.

Thank you Mike for for your speedy & clear response.
My question was posed because I wish to use the 64 bit W7 OS for video editing & I assume that, together with my quad core processor, it will give me a better editing experience. However, I currently have a dual boot system on one physical 500GB hard drive; partitioned as drive "C" containing Vista 32 bit & drive "W" containing W7 32 bit. Could you please tell me whether it is now possible to dual boot Vista 32 bit with W7 64 bit again both on the same physical hard drive?
stowey aka Ian.

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