diff --git a/install.ps1 b/install.ps1
index 06732bcc..0cd73eaa 100644
--- a/install.ps1
+++ b/install.ps1
@@ -11,7 +11,7 @@
 
     $ErrorActionPreference = "Stop"
     $defaultInstallUrl = "https://raw.githubusercontent.com/Abdess/retrobios/main/install.py"
-    $defaultInstallSha256 = "aa47489286d9f69a13b5e526fbf573eba9c1edc76ece9ca403b2a1952090c89a"
+    $defaultInstallSha256 = "dcf0c308a5a3176b66360e196d10b2ac678bda7f9245b22bc0cf43b0459a7d4d"
     $maximumInstallerBytes = 2MB
     $installerExit = 0
     $installer = if ($PSScriptRoot) { Join-Path $PSScriptRoot "install.py" } else { $null }
diff --git a/install.py b/install.py
index ba823e75..27c1b40f 100644
--- a/install.py
+++ b/install.py
@@ -8767,6 +8767,19 @@ def _open_from_folders(folders: list[Path]) -> None:
                     other_drives=[str(drive) for drive in index.other_drives])
 
 
+def _refuse_closed(dest: Path, named: str) -> None:
+    """End the run, with its name, on a folder above dest this user cannot open."""
+    closed = closed_folder(dest)
+    if closed is None:
+        return
+    message = closed_folder_words(dest, closed)
+    EVENTS.emit("error", stage="dest", reason="unreadable", platform="", message=message)
+    print(f"Error: {screen_text(message)}. Give this user access to it, run as "
+          f"its owner, or choose another folder than the one {named}.",
+          file=sys.stderr)
+    sys.exit(1)
+
+
 def _missing_dest(dest: Path, ask: bool, named: str = "named with --dest") -> None:
     """Say that a --dest folder does not exist before anything goes there.
 
@@ -8777,14 +8790,7 @@ def _missing_dest(dest: Path, ask: bool, named: str = "named with --dest") -> No
     at a terminal the run asks first, and the answer defaults to no. A
     folder above it this user cannot open ends the run with its name.
     """
-    closed = closed_folder(dest)
-    if closed is not None:
-        message = closed_folder_words(dest, closed)
-        EVENTS.emit("error", stage="dest", reason="unreadable", platform="", message=message)
-        print(f"Error: {screen_text(message)}. Give this user access to it, run as "
-              f"its owner, or choose another folder than the one {named}.",
-              file=sys.stderr)
-        sys.exit(1)
+    _refuse_closed(dest, named)
     if dest.exists():
         return
     nearest = dest.absolute()
@@ -9207,6 +9213,11 @@ def _install(args: argparse.Namespace, real_stdout: TextIO) -> None:
 
     if args.dest is not None and not listing:
         _missing_dest(args.dest, interactive and not (args.check or args.dry_run or args.yes))
+    elif not listing:
+        # A system_directory under /root read from retroarch.cfg, run without
+        # sudo: the case probe raised PermissionError before any line.
+        for _name, path in platforms:
+            _refuse_closed(path, "detected here")
 
     total_downloaded = 0
     total_up_to_date = 0
@@ -12495,7 +12506,7 @@ def _install_kind(path: Path) -> str:
                          ("/snap/", "Snap")):
         if marker in text:
             return word
-    if (path.parent / "retroarch.cfg").is_file():
+    if _is_file(path.parent / "retroarch.cfg"):
         return "portable"
     return ""
 
diff --git a/install.sh b/install.sh
index 77f62f89..c901cd7a 100755
--- a/install.sh
+++ b/install.sh
@@ -18,7 +18,7 @@ esac
 TEMP_INSTALLER=""
 TEMP_DIRECTORY=""
 DEFAULT_INSTALL_URL="https://raw.githubusercontent.com/Abdess/retrobios/main/install.py"
-DEFAULT_INSTALL_SHA256="aa47489286d9f69a13b5e526fbf573eba9c1edc76ece9ca403b2a1952090c89a"
+DEFAULT_INSTALL_SHA256="dcf0c308a5a3176b66360e196d10b2ac678bda7f9245b22bc0cf43b0459a7d4d"
 MAX_INSTALLER_BYTES=2097152
 
 cleanup() {
diff --git a/ports/shared/tui.txt b/ports/shared/tui.txt
index 0686399a..e7f2a4bb 100644
--- a/ports/shared/tui.txt
+++ b/ports/shared/tui.txt
@@ -876,6 +876,12 @@ rb_here() {
     # Ended by Start + Select or a signal: the player asked to leave, and no
     # button may be left to close a message.
     :
+  elif [ "$status" != "0" ] && [ "$(head -n 1 "$RB_STATE/tui.err" 2>/dev/null)" = "No button pressed, closing." ]; then
+    # Closed for want of a button: the mapper never opened the pad, so no A
+    # is coming. The error it closed is the next line, shown for
+    # RB_DEAD_WAIT seconds.
+    RB_MESSAGE_WAIT="$RB_DEAD_WAIT" rb_message \
+      "$(sed -n 2p "$RB_STATE/tui.err") The messages are in $RB_LOG."
   elif [ "$status" != "0" ] && [ -s "$RB_STATE/tui.err" ]; then
     # The first line of the farewell: the error screen it closes was read.
     rb_message "$(head -n 1 "$RB_STATE/tui.err") The messages are in $RB_LOG."
diff --git a/tests/test_handheld_launchers.py b/tests/test_handheld_launchers.py
index 7f3d71c2..3eef936d 100644
--- a/tests/test_handheld_launchers.py
+++ b/tests/test_handheld_launchers.py
@@ -484,6 +484,10 @@ if os.environ.get("FAKE_HOLD"):
     note("ui.ready")
     time.sleep(60)
     sys.exit(0)
+if os.environ.get("FAKE_IDLE_ERROR"):
+    # RETROBIOS_IDLE_EXIT on an error screen: the idle line, then the error.
+    print("No button pressed, closing.", file=sys.stderr)
+    print("Error: " + os.environ["FAKE_IDLE_ERROR"], file=sys.stderr)
 if os.environ.get("FAKE_ERROR"):
     print("Error: " + os.environ["FAKE_ERROR"], file=sys.stderr)
 sys.exit(int(os.environ.get("FAKE_CODE", "0")))
@@ -1197,6 +1201,19 @@ class ThePortMasterPort(unittest.TestCase):
         device.assert_mapper_gone()
         device.assert_console_restored()
 
+    def test_an_idle_close_on_an_error_names_the_error_at_once(self):
+        """The interface closed for want of a button: the mapper never
+        opened the pad, so no A can close a message. The error it closed is
+        named, for RB_DEAD_WAIT seconds, not the idle line for 300."""
+        device = self.device()
+        proc = device.run(["bash", self.script], FAKE_IDLE_ERROR="could not reach the file list",
+                          FAKE_CODE="1", RB_MESSAGE_WAIT="300", RB_DEAD_WAIT="1")
+        self.assertEqual(proc.returncode, 1)
+        self.assertLess(device.elapsed, 10)
+        self.assertIn("could not reach the file list", device.screen)
+        self.assertNotIn("No button pressed", device.screen)
+        device.assert_console_restored()
+
     def test_start_select_before_the_interface_handles_signals(self):
         """A SIGTERM before run_tui installs its handlers ends Python on the
         default action, status 143."""
diff --git a/tests/test_install_experience.py b/tests/test_install_experience.py
index 825ce6ee..5e15ae63 100644
--- a/tests/test_install_experience.py
+++ b/tests/test_install_experience.py
@@ -595,6 +595,44 @@ class AFolderThisUserCannotEnter(unittest.TestCase):
         self.assertIn(str(lock), errors[0]["message"])
 
 
+class ADetectedFolderUnderAClosedOne(unittest.TestCase):
+    """retroarch.cfg naming a system_directory under a folder this user
+    cannot open, with no --dest: the case probe raised PermissionError and
+    the run, and the interface before its first screen, ended on a
+    traceback. The refusal --dest gets is the one detection gets."""
+
+    @unittest.skipIf(os.name == "nt" or os.geteuid() == 0,
+                     "a folder without search permission is POSIX")
+    def test_it_is_refused_in_words(self):
+        with FakeRepository() as repo:
+            home = repo.root / "home"
+            lock = repo.root / "lock"
+            (home / ".config" / "retroarch").mkdir(parents=True)
+            lock.mkdir()
+            (home / ".config" / "retroarch" / "retroarch.cfg").write_text(
+                f'system_directory = "{lock / "system"}"\n')
+            env = {**repo.env(), "HOME": str(home), "XDG_CONFIG_HOME": str(home / ".config"),
+                   "RETROBIOS_OS": "linux"}
+            command = [sys.executable, str(REPO_ROOT / "install.py"), "--platform",
+                       "retroarch", "--no-input"]
+            os.chmod(lock, 0o000)
+            try:
+                runs = {name: subprocess.run(command + extra, env=env, capture_output=True,
+                                             text=True, timeout=60, stdin=subprocess.DEVNULL)
+                        for name, extra in (("check", ["--check"]), ("install", []))}
+                kinds = install.tell_apart([("retroarch", lock / "system", "RetroArch"),
+                                            ("retroarch", repo.dest, "RetroArch")])
+            finally:
+                os.chmod(lock, 0o755)
+        for name, proc in runs.items():
+            with self.subTest(run=name):
+                self.assertNotIn("Traceback", proc.stderr)
+                self.assertEqual(proc.returncode, 1, proc.stdout + proc.stderr)
+                self.assertIn(f"this user cannot open {lock} (Permission denied)",
+                              proc.stderr)
+        self.assertEqual(len(kinds), 2)
+
+
 class OutputToAFileAsksNothing(unittest.TestCase):
     """`install.py > log.txt` at a terminal: the menu went into the file
     and the run waited on an answer to a prompt nobody could see."""
diff --git a/wiki/installer.md b/wiki/installer.md
index 51f061a0..63c0693d 100644
--- a/wiki/installer.md
+++ b/wiki/installer.md
@@ -1387,7 +1387,7 @@ PowerShell as Administrator only for a protected folder.
 
 When a folder above the BIOS folder cannot be opened at all (`/root/...` run
 without `sudo`, a card mounted for another user), the run stops before it
-starts: `this user cannot open /root/.config (Permission denied), which holds
+starts: `this user cannot open /root (Permission denied), which holds
 /root/.config/retroarch/system`. The full-screen interface says the same on
 the folder screen and asks for another folder.