A family of Microsoft word processing software products for creating web, email, and print documents.
In the locked thread that you linked to (https://answers.microsoft.com/en-us/msoffice/forum/all/word-crashes-when-changing-the-margin/771981ea-4a4e-475c-a47d-15b33ec9b1e9), the original poster has posted a fix which worked for her. The fix is added as part of the original message:
To fix it:
I found that disconnecting the network restored control immediately and the narrow margin was achieved.
If that doesn't work for you, check which printer is set as the Windows default. Typically, if you don't have a physical printer, you would want a PDF virtual printer (PDF converter) set as the default. The driver called Microsoft Print to PDF is one possibility. See https://support.microsoft.com/en-us/windows/set-a-default-printer-in-windows-e10cf8b8-e596-b102-bf84-c41022b5036f.