Office 2024 and Microsoft 365 use the same underlying apps and installer on Mac, so it is normal for the installer and the apps (Word, Excel, etc.) to show Microsoft 365 branding even when the license is for Office 2024.
What is happening in this scenario is that the apps are still associated with the old Microsoft 365 subscription (from work) and are prompting to activate that subscription instead of using the new Office 2024 license. The fix is to remove the old Office/Microsoft 365 licensing and then sign in or activate with the new Office 2024 license.
Follow this approach:
- Remove the old Office/Microsoft 365 license from the Mac so it is no longer registered to the previous (work) account.
- Make sure the old work account is fully signed out of all Office apps.
- Start one of the Office apps (for example, Word) and activate using the account or method associated with the Office 2024 purchase (for example, the Microsoft account used to redeem the product key at https://microsoft365.com/setup, or the activation flow provided with the Office 2024 purchase).
Once the old license is removed and the new Office 2024 license is registered and used for activation, the same apps (Word, Excel, PowerPoint, etc.) will run as Office 2024 rather than requiring an Office 365 subscription, even though the UI may still show Microsoft 365 branding.
If activation still fails or continues to prompt for Office 365, completely uninstall Office from the Mac, remove any remaining Office-related data, then reinstall and activate again with the Office 2024 license.
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