Microsoft Visio Premium 10

Dear @Keith Beard

In this case, since you've lost your Microsoft Visio Premium 2010 product key, there's no legitimate way to recover the key itself.

If Visio is no longer installed, your best option is to look for the original purchase confirmation, installation media, certificate of authenticity, or any Microsoft account where the product may have been registered.

Please understand that Office 2010 products, including Visio Premium 2010, reached end of support. Microsoft support options and activation services for older products can be limited. For reference: End of support for Office 2010

Note: Since this is a user‑to‑user support forum, I don’t have the ability to access or investigate individual accounts, nor can I directly take action on Microsoft product features.

However, if recovery may not be possible, a practical option is to upgrade to Visio Plan 2. Visio Plan 2 provides the latest Visio desktop application, web access, ongoing security updates, and access to the newest templates and features. It also eliminates the need to manage an older Visio 2010 product key. For reference: Upgrade from Visio 2010 to Visio Plan 2

I hope the information shared is helpful. If you have any questions, please feel free to reach out.

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