Problem
Exporting or Previewing on Windows machines is failing without any clear reason. Additional symptoms could be InDesign crashing upon executing those tasks.
Cause
A virus scanner, firewall or anti-malware app could block the Twixl Publisher Helper app and that app is needed to take care of any Export of Preview action.
Solution
Make sure that any type of virus scanner, firewall or anti-malware app has the following app whitelisted:
C:\Program Files (x86)\Twixl Publisher\TwixlPublisherHelper.exe