title: What causes the "Schema Conflict when Loading a File" in Revit?
body: <p>When I open a Revit file, I get an error titled "Schema Conflict when Loading a File". The schema conflict is with my own schema. What could be different between the two schemas that could cause this error?</p>
  
  <p>The full text of the error is:</p>
  
  <blockquote>
    <p>Schema Conflict when Loading a File</p>
    
    <p>The file being loaded is causing a conflict with existing data in the
    model. What do you want to do?</p>
    
    <p>The file contains data of schema "XYZ" (from "ABC"), which has the
    same ID as a different schema already in memory. If the file is
    loaded, the existing data will be erased from the model.</p>
  </blockquote>
  
  <p><a href="https://i.stack.imgur.com/XFF86.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/XFF86.png" alt="enter image description here"></a></p>