Hi, Athanasios NESTORAS
Office 2016 for Mac is no longer supported, so the download link is not always easy to find from the normal Office pages. The key also needs to be linked to the Microsoft account that was originally used to redeem it. Office 2016 support has ended, but redeemed products can still usually be reinstalled from the associated account.
Here are some suggestions you can try:
First, go to Microsoft Services & subscriptions and sign in with the Microsoft account used when the key was first redeemed. If Office 2016 for Mac is listed there, choose Install. If the key has never been redeemed, go to Office setup, sign in, and enter the 25-character key. Once a key has already been redeemed, you should reinstall from the Microsoft account rather than entering the key again.
If you specifically need the Office 2016 for Mac 16.16 installer, Microsoft’s own support article provides these older installer links: Office 2016 for Mac Home & Business or Volume License, and Office 2016 for Mac Home & Student. Make sure you pick the correct one, because Home & Student does not include Outlook.
It is recommended that you avoid random third-party download sites, especially if they ask for another key or activation tool. If the product does not appear under Services & subscriptions, contact Microsoft Support with the purchase proof and key.
Please be advised that this is a user-to-user support forum. Moderators and contributors, including external Microsoft employees, are not allowed to directly interfere with Microsoft product features or access back-end systems. Our role is limited solely to providing technical guidance on reported incidents, requests, or ideas.
Thank you for your patience in reading, I hope this information has been helpful to you.
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