Hi @Eric liu
As your issue is related to VSTO add-in instead of Word app, to help you better, it's recommended to post a new thread on other forums of following link.
https://developer.microsoft.com/en-us/word#wordcommunity
The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction with us. Thank you for your understanding.
Personally I suggest you install C/C++ VS runtime to have a check.
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