Hello JesseWonnink,
Thank you for bringing this to our attention. We appreciate that you've taken the time to post your concern here in Microsoft Community Forum.
We understand that you’re having trouble installing your preferred proofing language in Word . Let’s check on this together and find ways to address this matter.
Now in order for us to better assist you on this matter I need to ask:
- What proofing language are you trying to install?
- Have you installed it on your machine too?
- what version and edition of Word you’re using? Please follow the screenshot I have provided below. ( Provide us a screenshot of it)

Now in order for us to better assist you on this matter I need to ask for a screen recording of the issue. We want to see the actual issue happening on your end in that way we can also replicate the issue here on our end to provide you answer or resolution and also to make sure that we will not missing anything. Please make sure all the things you've performed will be included on the video.
Record your screen using Microsoft PowerPoint click here: -- Record your screen in PowerPoint . You can also send it via InPrivate message. I already sent you a private message please check your email and click on the link to reply via InPrivate message.
Please upload your PowerPoint file to OneDrive click on share then click copy link and provide it here when you reply.
Here's how you upload files to OneDrive. -- Upload and save files and folders to OneDrive
To share or copy the link of your file, please click here. -- Share files and folders in OneDrive (personal)
- Have you followed the steps I have provide below?
Note: If you're using Office 365 and the commands available are different from what's shown here, expand the Configure Office language for Office 2016 or earlier section and follow the instructions there.
In Office, the language options are in the Office Language Preferences dialog box. The display and authoring languages can be set independently. For example, you could have everything match the language of your operating system, or you could use a combination of languages for your operating system, authoring, and display.
To configure the display language:
- Within any Office application, select File > Options > Language.
- Under Office display Language, make sure the display language you want Office to use is listed.
3. Select the language you want, and then select Set as Preferred. If you want your Office display language to match the display language you have for Windows, select Match Microsoft Windows [Language].
4. If the language you want is not listed, select Install additional display languages from Office.com and follow the instructions there.
To configure the authoring and proofing language:
- Within any Office application, select File > Options > Language.
- Under Office authoring languages and proofing, make sure the language you want to use for authoring your document is listed.
3. If the language you want appears in the list, select it, and then select Set as Preferred. If the language you want is not listed, select Add a language, and then follow the instructions in the Add an authoring language dialog box.
4. If the language accessory pack includes proofing tools for that language, its status appears as Proofing installed. If the status is Proofing available, click the link to install the proofing tools.
Please check this support article: Change the language Office uses in its menus and proofing tools
We look forward to your response.
Sincerely,Juhn Jac,Consumer M365 Forum Moderator