Why isn't my Knowledge Article Visible on my Community?

Knowledge on Communities is great, but is a complete PITA to set up. There are so many reasons why your articles may not be displaying. 

Structural Setup

First, is the community set up right - go through Setting up Knowledge on Communities to make sure you have not missed one of the vital steps. 

• Is the Article Detail page visible to the Guest User
  • See Audience, Page Variations settings
• Does the Guest User Profile have Read access on the Object for the Article Type
  • And the Custom Fields on the Article Type that displays the data that the Guest User needs to see. 

Data Setup

• Are the Data Categories visible to the Guest User Profile
• Does the Guest User Profile have access to ALL the Data Categories that have been set on the Article. 
  • See Salesforce Help https://help.salesforce.com/articleView?id=category_visibility_whatis.htm&type=0for a full explanation of who can see what.
• Has the Article been assigned to a Topic

Testing

• Can you navigate to the Article via the URL directly
• Can you search on the Article
• Does it appear in the Article Topic list.