Issue Description
You have a Door/Window Schedule, and the Related Zone (the Zone to which the door/window either opens into or belongs to) field is empty or Undefined.
Solution
Here is a Checklist to help you find the cause of the issue.
1. The zone was created manually, and its construction method needs to be changed to Inner Edge or Reference Line.
2. The Zone has no closed polygon due to Renovation status inconsistencies and/or reference lines of walls are not connected. Make sure that the Door, Wall and Zone all have the same Renovation Status (Existing, Demolished, New).
3. There is another Archicad element in front of the door/window that is acting as Zone boundary. Therefore, the Zone is not touching the door/window.
4. The edge of the Zone must align precisely with the face of the wall that the door is placed in.
5. The Door settings under [Door Name] Settings > Descriptions must have the checkbox set accordingly [Door belongs to the Zone into which it swings] - This can vary depending upon the placement and swing direction of the door.
6. The Zone does not have the same height as the Wall and Door.
7. There should only be one Zone occupying the space adjacent to the Door/Window, regardless of duplicates having layers turned on/off.