Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Your 365 "Product Key" is one time use. After you use it to activate your subscription, on the new computer you just have to log in to the MyAccount site and find the "Install" button. That's all it takes.
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Here are the MS instructions:
Install Office- Download and install or reinstall Microsoft 365 or Office 2021-2010 on a PC or Mac
On this page on the left side of the page, pick the appropriate Office version. Near the top of the page pick the appropriate tab PC or Mac.
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If you are reinstalling Office, you have already redeemed a product key, or you are installing Office at work or school and know you have a license, then go to the section sign in to download and install Office.
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However, if this is the first time you're installing Office, you may have some pre-installation steps to do first. Expand the Learn more section below for more info.
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