Dear Harro de Jong1,
Thank you for posting in Microsoft Community. We are happy to help you.
I understand that you have a concern on adding a new proofing language taking so long and possible downloading the entire Office installer. Apologies for the inconvenience caused to you by this behavior. Before moving forward, we need more detailed information about the situation you are experiencing.
Kindly share with us the information below:
What is the version of your Word application?
May I know if you have language pack installed?
How many times you tried to add new proofing language and experience the same behavior?
Possible reason is the Office is trying to update or repair or install the language pack but yet to be confirmed. It would be great if you can provide a screen shot of the process.
We look forward to your response. Thanks for your cooperation. Stay safe and healthy always.
Sincerely,
Zee | Microsoft Community Moderator
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