1. In Community Builder, click .
2. Click Page Management.
3. Find Case Detail in the Name column, and make sure that the active page assigned to it is either Chatter Case Detail (the default) or Record Detail.If you change the active case detail page, publish your change.Important If the community case feed is enabled and you use Basic Case Detail as your active case detail page, external users only see case comments—notChatter posts or emails—in their case feed. This gives external users far less visibility into their cases. To give users a full view of their case interactions, use Chatter Case Detail or Record Detail as your active case detail page.