CWYW not formatting in-text references - unhelpful error message

Sorry to post again so soon, but searching the forum hasn’t provided any solutions.

I randomly started having trouble inserting references into my document. The reference appears unformatted and an alert box pops up with just the text “☐”.

What I have tried so far:

  • Computer restart.
  • Using a new empty document.
  • Enabling/disabling instant formatting.
  • Deleting recently added references from endnote web.