@박소연 ,
I have some questions to confirm more information to help me understand your issue better.
- What version of Office applications are you using now?
Please go to Word > File > Account > Product Information, check the version name of Office and share with us, such as Microsoft 365 apps for enterprise. - What's the type of account you login to Office?
Is it a personal account or the account that your school or other organization administrator assigned? - Where do you want to save this file? Do you want to save this file to cloud service, such as OneDrive, OneDrive for Business?
Please save this file to local computer or other location to check this issue.
According to the message (translated by Google), it seems that you use one business feature which needs an organization account, but you login to a personal account, or some previous existed credentials for personal account caused this issue.
I am looking forward to your reply.
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