Can I upgrade 32 bit Win 7 to 64 bit with OEM product key? RRS feed

  • Question

  • Hi, 

    Here I am all talking about Win 7 Home Premium version.

    My Thinkpad T410 had Windows 7 32 bit installed. It does not come with a Win 7 DVD but only recovery disks.

    I want to install Windows 7 64 bit. Before I start, I saved the product key for the original 32 bit win7.

    After I installed win 7 64 bit (download from microsoft store/mydigitallife ),  I input the product key I took from the original 32 bit but it does not work. My product key is like:

    xxxxx-OEM-xxxxxxx (the position of OEM may be different).

    Now I am on 3 days trial. Do I have to buy another product key? I thought the 32 bit key should work.

    Thank you,


    Monday, December 23, 2013 7:48 PM


All replies

  • If your computer came installed with Windows 7, turn your computer off and take off the battery. The Product key should be on a Windows 7 sticker. If it is not there, check and see if any other documentation came with the computer when you purchased it. You may be able to contact the manufacturer but I don't believe they keep a record of that.

    As far as upgrading though, you can upgrade from 32bit to 64bit. Make sure you install the correct version though - for example if you have the 32bit key for home premium, install the 64bit version of home premium.

    The OEM activation key is misleading. The OEM is the license, not the actual key. I always run a belarc before upgrading or rebuilding a PC. This tool will audit and provide you serial keys for all your purchased software. (It's free and simple)


    Monday, December 23, 2013 8:37 PM
  • The license of the OS you purchased from Lenovo is tied to the Operating System and that specific PC. It is not allowed to be transferred.

    From the licensing FAQ:

    A customer who wants you to reinstall Windows must provide recovery media from the direct OEM, because the software is licensed to the customer for use on that PC by that OEM. You cannot use your own OEM System Builder media to reinstall the operating system, or any other version of media (e.g., TechNet, MSDN, Action Pack, etc.), because these versions differ from the original OEM Windows license your customer acquired from the direct OEM. A customer who doesn't have a backup copy of the software for reinstallation will need to contact the original OEM and request replacement recovery media; you can use that media to reinstall the operating system on that machine.

    Tuesday, December 24, 2013 4:49 PM
  • Bill

    Your computer came with OEM, your 64 bit was not OEM.  Your key will not work.  Buy a new key or restore back to the original OS.

    Wanikiya and Dyami--Team Zigzag

    • Marked as answer by ZigZag3143x Monday, January 6, 2014 5:40 PM
    Tuesday, December 24, 2013 5:10 PM
  • You can find the product key in the battery bay on the certificate of authenticity (COA), as mentioned by BetaJake. Note the the product key doesn't contain OEM anywhere. If it doesn't work, you can contact the Lenovo support and request for a 64-bit DVD. The product key remains the same for 32-bit and 64-bit releases.

    COA looks like this:

    The product key can be found after "Product Key: " in the format xxxxx-xxxxx-xxxxx-xxxxx-xxxxx (25 digits). 

    Balaji Kundalam

    Wednesday, December 25, 2013 5:14 PM
  • Hi,

    Since you own an OEM version of a 32-bit version of Windows 7, your license key will not function on a 64-bit version of Windows 7. You will require either another OEM license key which is suitable for a 64-bit version of Windows 7, or you will need to purchase a retail version of Windows 7, which includes the installation media and license key for both the 32-bit as well as the 64-bit version of Windows 7.

    For more information, please see:

    Using win7 32-bit license key to activate a win7 64-bit installation


    Hope this helps,

    Ada Liu
    TechNet Community Support

    • Marked as answer by ZigZag3143x Monday, January 6, 2014 5:39 PM
    Thursday, December 26, 2013 2:03 AM
  • Bill,

    Have you found the resolution for this issue? Please keep us updated.

    Thank you,


    Monday, January 6, 2014 5:22 PM
  • I think most of the folks commenting have never tried this. They seem to be wrong!! I just recently decided to upgrade my memory in my Dell Inspiron 1400 from the OEM 4 gb RAM, on the Win 7 Home Premium 32 bit system. After installing the 8gb memory, I HAD to have a 64bit system to use it all. I simply found the Win 7 HP English version i wanted (Same as what I had) JUST in 64bit version. Did the whole flash to USB, etc, then booted from my flash drive (instead of media discs) , and have been running 64 bit for the past week.

    Just today I was surprised to see a prompt for authentication, a window had popped up asking for my product key again.

    My product key is under my battery, OEM version of windows. Not a retail version.

    I simply re-entered this product key, and it did it's thing. About 45 seconds later it said "Key accepted" and to enjoy my genuine Microsoft product. So far so good, and have found other sources say that, even with an OEM windows activation key, either 32 or 64 bit can be used with it. You wont know till you try, and you can always go back to 32 if it doesnt work. To hell with the nay sayers... it worked for me!

    • Proposed as answer by Martin Lewise Wednesday, July 18, 2018 9:58 PM
    Tuesday, July 25, 2017 5:49 PM
  • I was reluctant to try, but ended up doing it thanks to your post. It also worked without any problems for me.

    I had a laptop with pre-installed, OEM 32 bit 7 Home Premium. I downloaded the 64 bit Windows 7 DVD image and installed the 64 bit version of the same OS.

    Then I was able to activate it using the same OEM license key on the sticker.

    Saturday, January 12, 2019 10:56 PM