diff --git a/src/aare/gui/panels/file_path_panel.py b/src/aare/gui/panels/file_path_panel.py
index 7af162b3..a8ed8a28 100644
--- a/src/aare/gui/panels/file_path_panel.py
+++ b/src/aare/gui/panels/file_path_panel.py
@@ -144,23 +144,11 @@ class FilePathPanel(QWidget):
 
         base += "run" if file_prefix == "" else file_prefix
 
-        # Find next free run number using effective dataset path
-        rn = run_number
-        while True:
-            candidate_base = self._expand_macros(base, rn)
-            if not self._exists_for_run(candidate_base):
-                break
-            rn += 1
-            if rn > self.run_number_edit.maximum():
-                break
-
-        if rn != run_number:
-            self.run_number_edit.blockSignals(True)
-            self.run_number_edit.setValue(rn)
-            self.run_number_edit.blockSignals(False)
-
+        # Literal: the name is exactly what the fields say. No silent skip to
+        # the next free run here, or the click-time guard below never sees a
+        # clash; the label just turns red until the user (or the guard) acts.
         # Store the GUI’s base (without applying scan-kind transforms) for wiring into requests later
-        self._filename = self._expand_macros(base, rn)
+        self._filename = self._expand_macros(base, run_number)
 
         # Preview label shows the effective path (what will be written)
         effective = self._effective_dataset_base(self._filename)
@@ -240,23 +228,20 @@ class FilePathPanel(QWidget):
     def file_path_error_box(self, scan_kind: str) -> bool:
         """Click-time guard for the Run buttons: True when the run may start.
 
-        The scan kind is set directly, not via set_scan_kind(): that calls
-        update_filename(), which silently skips to the next free run number,
-        so the existence check below could never fire and the user was never
-        told the file was already there.
+        On a clash: bump the run number by one, tell the user, refuse the run.
+        The next click checks the new name again, so nothing is ever skipped
+        without the user seeing it.
         """
         self._scan_kind = scan_kind
-        exists = self._exists_for_run(self.filename)
+        self.update_filename()  # label/path for the clicked kind (screening vs rotation)
+        if not self._exists_for_run(self.filename):
+            return True
         path = self.effective_path_for_base(self.filename) + "_master.h5"
-        # Refresh the label for the clicked kind; on a clash this also moves
-        # the run number to the next free one, as every edit already does.
-        self.update_filename()
-        if exists:
-            QMessageBox.warning(
-                self,
-                "File exists",
-                f"File already exists:\n{path}\n\n"
-                f"Run number moved to {self.run_number_edit.value()}.",
-            )
-            return False
-        return True
+        self.increment_run_number()
+        QMessageBox.warning(
+            self,
+            "File exists",
+            f"File already exists:\n{path}\n\n"
+            f"Run number increased to {self.run_number_edit.value()}.",
+        )
+        return False
diff --git a/tests/unit/gui/test_data_collection_settings.py b/tests/unit/gui/test_data_collection_settings.py
index 72f50ddc..a6c54c92 100644
--- a/tests/unit/gui/test_data_collection_settings.py
+++ b/tests/unit/gui/test_data_collection_settings.py
@@ -518,10 +518,16 @@ def test_run_is_blocked_with_a_popup_when_the_file_exists(file_panel, monkeypatc
     boxes = []
     monkeypatch.setattr(QMessageBox, "warning", lambda *a, **k: boxes.append(a))
 
+    # Editing never skips a taken run silently: the name stays literal and
+    # the label only turns red.
+    file_panel.set_scan_kind("rotation")
+    assert file_panel.run_number_edit.value() == 1
+    assert file_panel.file_name_label.styleSheet() != ""
+
     assert file_panel.file_path_error_box(scan_kind="rotation") is False
     assert len(boxes) == 1
     assert "data/d/x_001_master.h5" in boxes[0][2]
-    # The panel moved on to the next free run, so the next click can go ahead.
+    # Run number went up by one, so the next click can go ahead.
     assert file_panel.run_number_edit.value() == 2
     assert file_panel.file_path_error_box(scan_kind="rotation") is True
     assert len(boxes) == 1