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I purchased a Lenovo ThinkBook 16, which was delivered with Office 2024. Since Office 2024 does not include Outlook, I installed Office Home & Business 2016, which includes Outlook.
I am quite comfortable using Outlook 2016 from Office Home & Business, as I primarily use Outlook for personal purposes. I therefore installed Office Home & Business 2016 and successfully activated it using my product key.
Under the Product Information section in Office applications such as Word and Excel, there is a “Switch License” option. This allows me to switch back to Office 2024. However, as soon as I switch to Office 2024, Outlook 2016 becomes unlicensed and I am prompted to subscribe to Microsoft 365 instead of being able to continue using my activated Outlook 2016 license.
If I enter the Office Home & Business 2016 product key again, Outlook 2016 becomes activated and works normally. However, this means that I have to repeatedly enter my Office Home & Business 2016 product key whenever I want to use Outlook after switching to Office 2024.
How can I avoid having to enter the Office Home & Business 2016 product key repeatedly while continuing to use Office 2024 for applications such as Word and Excel and Outlook 2016 for email?
Using Classic Outlook on Windows for personal email, calendar, and contact management
@Dinesh said
How can I avoid having to enter the Office Home & Business 2016 product key repeatedly
In most cases, if the KB5002907 bug is what caused your problem, you only have to re-register the older Office version once. After that it sticks.
Your situation sounds more like the problems you will see with any "side by side" setup of two different Office versions.
The only stable setup I have seen is when the 2016 version is an MSI install (not Click-To-Run like 2024), you only install Outlook from 2016, and then do the 2024 install. But it's still tricky.
Another option is a perpetual license for Classic Outlook for Windows standalone. As far as I can tell, this should be compatible with Office 2024. But I have not personally tested.
https://www.microsoft.com/en-us/microsoft-365/p/outlook/cfq7ttc0pbmd
And, of course, there is always free New Outlook for Windows.
https://apps.microsoft.com/detail/9nrx63209r7b
The installed Office 2024 version came with the laptop. Yes, I did install the 2016 version on the new laptop using the product key provided with the purchase of Home and Business 2016 (re-registration). Are you suggesting that I should reinstall Office 2024 using the product key supplied with the laptop at the time of purchase?
@Dinesh said
Are you suggesting ...
Not suggesting anything at this point. Need to know if your 2016 is a MSI or Click-To-Run.
The requirement to enter the key for your 2016 Office is related to an active known issue right now, due to a recent update KB5002907
Microsoft communicates it here, and you can also bookmark this page to check back for mitigation/fixes update.