Hi Diane Hughes
Thank you for reaching out to Microsoft Q&A Forum and sharing details of your issue with activating Microsoft Office Professional 2010.
The error referencing Access.en-us/branding.xml typically indicates a corrupted or missing file within your Office installation. It’s important to note that Microsoft Office 2010 reached end of support in October 2020, so official downloads and updates are no longer available through standard Microsoft channels. While there isn’t a specific downloadable “fix” for this issue, based on my research, here are some related troubleshooting steps that may help resolve your activation problem:
Start by closing all open Office programs like Word or Access. Then refer to this article to Repair an Office application. After it's finished, please restart your computer and then try to activate Office again.
The next step is a complete reinstallation. Please know that for this, you will need your original 25-character Product Key and your installation media (the disc or downloaded file). You would need to uninstall Office 2010 from the Control Panel, restart your computer, and then reinstall it from scratch. Please note: Make sure to back up all databases before reinstalling.
Run Windows Update to confirm that any remaining Office 2010 updates have been installed. If updates fail, you may need to manually download the last available Service Pack (SP2) from the official Microsoft Download Center: Download Service Pack 2 for Microsoft Office 2010 (KB2687455) 32-Bit Edition from Official Microsof…
Since Office 2010 is no longer supported, continuing to use unsupported software can expose your system to vulnerabilities and compatibility issues with newer Windows versions. I strongly recommend considering an upgrade to a modern version to ensure you have the latest features and critical security protection. Your options include the subscription-based Microsoft 365 or a one-time purchase of Office 2021. For your reference: Plan an upgrade from older versions of Office to Microsoft 365 Apps - Microsoft 365 Apps | Microsof…
I hope one of these steps gets you back up and running. Please let us know how you get on, as your feedback can help others in the community facing the same problem.
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