diff --git a/crates/engine/src/cmd/sheet.rs b/crates/engine/src/cmd/sheet.rs
index 473a877bb..32122abd6 100644
--- a/crates/engine/src/cmd/sheet.rs
+++ b/crates/engine/src/cmd/sheet.rs
@@ -298,7 +298,7 @@ fn check_push_off_sheet(s: &Session, sheet: usize, axis: Axis, at: u32, count: u
     if let Some(u) = s.doc()?.wb.sheet(sheet).and_then(|sh| sh.used_range()) {
         let last = if axis == Axis::Rows { u.end.row } else { u.end.col };
         if last >= at && last as u64 + count as u64 >= limit as u64 {
-            return Err(EngineError::Other("To prevent possible loss of data, Excel cannot shift nonblank cells off of the worksheet.".into()));
+            return Err(EngineError::Other("To prevent possible loss of data, GridCraft cannot shift nonblank cells off of the worksheet.".into()));
         }
     }
     Ok(())
@@ -521,7 +521,7 @@ fn insert_cells(s: &mut Session, p: &Json) -> Result<Json> {
             RangeRef::new(CellRef::new(r.start.row.max(MAX_ROWS.saturating_sub(r.height())), r.start.col), CellRef::new(MAX_ROWS - 1, r.end.col))
         };
         if sh.cells.iter_range(doomed).any(|(_, x)| x.formula.is_some() || !x.value.is_empty()) {
-            return Err(EngineError::Other("To prevent possible loss of data, Excel cannot shift nonblank cells off of the worksheet.".into()));
+            return Err(EngineError::Other("To prevent possible loss of data, GridCraft cannot shift nonblank cells off of the worksheet.".into()));
         }
     }
     let right = shift == "right";
diff --git a/crates/engine/src/tests.rs b/crates/engine/src/tests.rs
index b61d85c76..7250d3749 100644
--- a/crates/engine/src/tests.rs
+++ b/crates/engine/src/tests.rs
@@ -2007,6 +2007,15 @@ fn a_whole_column_table_without_headers_stays_on_the_sheet() {
     assert!(e.to_string().contains("pushed off the end"), "{e}");
 }
 
+#[test]
+fn inserting_a_column_next_to_far_right_data_names_gridcraft_in_the_refusal() {
+    let mut sess = s();
+    sess.execute("cell.set", json!({"cell": "XFD1", "input": "2"})).unwrap();
+    let e = sess.execute("home.insertColumns", json!({"cols": "A:A"})).unwrap_err();
+    assert!(e.to_string().contains("GridCraft cannot shift nonblank cells"), "{e}");
+    assert!(!e.to_string().contains("Excel"), "{e}");
+}
+
 #[test]
 fn inserting_cells_refuses_to_push_values_off_the_sheet() {
     for (shift, edge, last_fit, last_ok) in [("right", "XFD1", "XFC1", "XFD1"), ("down", "A1048576", "A1048575", "A1048576")] {
@@ -2015,6 +2024,7 @@ fn inserting_cells_refuses_to_push_values_off_the_sheet() {
         sess.execute("cell.set", json!({"cell": edge, "input": "2"})).unwrap();
         let e = sess.execute("home.insertCells", json!({"range": "A1", "shift": shift})).unwrap_err();
         assert!(e.to_string().contains("loss of data"), "{e}");
+        assert!(e.to_string().contains("GridCraft") && !e.to_string().contains("Excel"), "{e}");
         assert_eq!(v(&sess, "A1"), Value::Number(1.0));
         assert_eq!(v(&sess, edge), Value::Number(2.0));
         // A value that still fits moves to the last valid cell.