The problem is fixed in the latest release of Acrobat. Update your Acrobat DC or Arobat 2017 to the latest version. To automatically update from Acrobat, choose Help > Check for updates, and then follow the steps in the Updater window to download and install the latest updates.
When you try to convert a Word document to PDF using Acrobat, the conversion fails with the following error message.
Reason: The error occurs after January 18, 2018, update for Office 2016 for Mac.
Acrobat team is working to resolve the problem. Meanwhile, as a workaround, roll back the Office 2016 update to its December 2017 version - 15.41.0 (17120500). You can download it from the following link: 15.41.0 (17120500).