diff --git a/l4d2host/instances.py b/l4d2host/instances.py
index 59a293e..8128114 100644
--- a/l4d2host/instances.py
+++ b/l4d2host/instances.py
@@ -135,14 +135,17 @@ def stop_instance(
         passthrough=passthrough,
         should_cancel=should_cancel,
     )
-    emit_step("unmounting runtime overlay...", on_stdout, passthrough)
-    run_command(
-        ["fusermount3", "-u", str(root / "runtime" / name / "merged")],
-        on_stdout=on_stdout,
-        on_stderr=on_stderr,
-        passthrough=passthrough,
-        should_cancel=should_cancel,
-    )
+    emit_step("unmounting runtime overlay (if mounted)...", on_stdout, passthrough)
+    try:
+        run_command(
+            ["fusermount3", "-u", str(root / "runtime" / name / "merged")],
+            on_stdout=on_stdout,
+            on_stderr=on_stderr,
+            passthrough=passthrough,
+            should_cancel=should_cancel,
+        )
+    except subprocess.CalledProcessError:
+        pass
     emit_step("stop complete.", on_stdout, passthrough)
 
 
diff --git a/l4d2host/tests/test_lifecycle.py b/l4d2host/tests/test_lifecycle.py
index 84d6bd4..5c369d1 100644
--- a/l4d2host/tests/test_lifecycle.py
+++ b/l4d2host/tests/test_lifecycle.py
@@ -96,6 +96,27 @@ def test_delete_stopped_instance_removes_dirs(tmp_path: Path, monkeypatch: pytes
     assert ["sudo", "-n", "/usr/local/libexec/left4me/left4me-systemctl", "stop", "alpha"] in calls
 
 
+def test_stop_succeeds_when_unmount_fails(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    fusermount_calls: list[list[str]] = []
+
+    def fake_run_command(cmd, **kwargs):
+        del kwargs
+        if cmd and cmd[0] == "fusermount3":
+            fusermount_calls.append(list(cmd))
+            raise subprocess.CalledProcessError(
+                returncode=1,
+                cmd=list(cmd),
+                stderr="fusermount3: failed to unmount /var/lib/left4me/runtime/alpha/merged: Invalid argument",
+            )
+
+    monkeypatch.setattr("l4d2host.instances.run_command", fake_run_command)
+    monkeypatch.setattr("l4d2host.service_control.run_command", fake_run_command)
+
+    stop_instance("alpha", root=tmp_path)
+
+    assert fusermount_calls, "stop must always attempt fusermount3 -u (no preflight)"
+
+
 def test_delete_succeeds_when_unmount_fails(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
     fusermount_calls: list[list[str]] = []