Office Professional 2007 is a perpetual, disk‑based product and is not the same as Microsoft 365 (Office 365). A 2007 product key cannot be used to download or activate Microsoft 365, and it cannot be converted into a Microsoft 365 subscription.
To use the license that is already owned (Office 2007):
- Install from the original Office 2007 media
- Insert the Office 2007 CD.
- If setup does not start, open the CD drive and run
SETUP.EXE.
- When prompted, enter the Office 2007 product key from the CD case/packaging.
- Accept the license terms and complete setup.
- For details, see the steps under Install Office 2007 in the documentation.
- Activate Office 2007
- Open Word, Excel, PowerPoint, or Access.
- Select Microsoft Office Button > Options > Activate Microsoft Office.
- For other Office 2007 apps, select Help > Activate Product.
- Follow the prompts to complete activation.
Note that Office 2007 is out of support, but it can still be installed and used with a valid product key. The “Sign in to set up Office” web portal and product‑key redemption flow are for Microsoft 365 and newer Office versions, not for Office 2007. That is why entering the 2007 key in the web portal does not complete properly.
If a newer, subscription‑based Office (Microsoft 365) is desired instead of Office 2007, a separate Microsoft 365 subscription purchase is required; the 2007 key cannot be reused for that.
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