#NULL!
Two ranges were intersected but do not overlap.
What it means
A space between two references is the intersection operator. When the two ranges share no cells, the intersection is empty and the formula returns #NULL!.
How to fix it
- Add the missing comma or colon between the references.
- If you meant an intersection, use ranges that actually share cells.
Common causes
- A missing comma between arguments, e.g. =SUM(A1:A2 B1:B2) instead of =SUM(A1:A2, B1:B2).
- A deliberate intersection of ranges that do not overlap.
A formula that produces it
=SUM(A1:A2 B1:B2)