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Office 2010 and later include a vbs-script which will reveal the last 5 characters of your Product Key. Find license keys for Office 2010, Office 2013, Office 2016, Office 2019 and Office 2021 via a script You can still look up these license keys in the Services & Subscriptions section of your Microsoft Account. The same applies to Office 2016, Office 2019 and Office 2021 licenses that are linked to your Microsoft Account. Note: Microsoft 365 installations don’t require a license key as they activate automatically when you log on to Office with your Microsoft Account. However, for either version there is no need to completely reinstall Office.
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The proper method to determine or change the Product Key depends on your version of Office or Outlook. While you could simply try one of your Product/License Keys and see if it gets accepted, it’s not a very sophisticated approach. How can I find out which license I've used for which computer and how can I change the key if needed? I've got several licenses for Office and Outlook but I'm not sure which one which ones I've used and which ones are free.
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