diff --git a/CLAUDE.md b/CLAUDE.md
index 263f76b..db2be07 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -140,7 +140,10 @@ persistence) → GUI (Qt widgets that read the manager and connect to its signal
   floor between versions), `music_folder_rel` relative to the data dir (the
   portable one, same trick as `Track.location`), and `music_folder_set_at`, a
   stamp so a merge prefers the newest *setting* rather than the newest *file*.
-  `resolve()` tries rel → legacy → the per-machine override in `config.json`,
+  `resolve()` tries rel → legacy → the per-machine override in `config.json`
+  (both `music_folder_override` *and* the older `music_root` that
+  `--music-root … --save-config` writes — an imported library already
+  knows where its music is on this machine, so don't ask),
   and every candidate must **exist** — the override is consulted last so a
   machine that once needed one isn't pinned to it forever. Two rules that bite:
   `LibraryManager.set_music_folder` must call `mark_library_settings_dirty()`
diff --git a/lintunes/__init__.py b/lintunes/__init__.py
index cdecade..ca5e082 100644
--- a/lintunes/__init__.py
+++ b/lintunes/__init__.py
@@ -1,3 +1,3 @@
 """LinTunes — iTunes-style music library manager and player for Linux."""
 
-__version__ = "0.12.0"
+__version__ = "0.12.1"
diff --git a/lintunes/music_folder.py b/lintunes/music_folder.py
index b176c77..c0127fc 100644
--- a/lintunes/music_folder.py
+++ b/lintunes/music_folder.py
@@ -10,7 +10,9 @@ single place that decides, in this order:
    machine even when the absolute paths are not.
 2. ``music_folder`` — the legacy absolute value. Libraries written before 0.10,
    and libraries last written by an older LinTunes, only have this one.
-3. The machine-local override in ``~/.config/lintunes/config.json``.
+3. The machine-local override in ``~/.config/lintunes/config.json`` — either
+   ``music_folder_override`` (set by the folder prompt) or the older
+   ``music_root`` that ``--music-root … --save-config`` has always written.
 
 The override is consulted **last, not first**, on purpose. If it won outright, a
 machine that once needed an override would be pinned to it forever and would
@@ -32,6 +34,13 @@ from lintunes.paths import to_absolute
 # Keys in the per-machine config.json (never synced).
 OVERRIDE_KEY = "music_folder_override"
 PROMPT_SEEN_KEY = "music_folder_prompted"
+# The same fact under its pre-0.10 name: `--music-root … --save-config` has
+# always written this machine's media folder here, and the importer stores it as
+# `library.music_folder`. Every library set up that way therefore has the right
+# answer sitting in config.json, and ignoring it meant a machine that mounts the
+# drive somewhere else was asked to locate a folder it had already been told
+# about. Read-only — nothing writes it back, so the newer key stays canonical.
+LEGACY_OVERRIDE_KEY = "music_root"
 
 
 @dataclass(frozen=True)
@@ -73,8 +82,10 @@ def resolve(library, data_dir, config=None) -> Resolution:
         if found is not None:
             return Resolution(found, "legacy", legacy)
 
-    override = config.get(OVERRIDE_KEY, "")
-    if override:
+    for key in (OVERRIDE_KEY, LEGACY_OVERRIDE_KEY):
+        override = config.get(key, "")
+        if not override:
+            continue
         found = _existing_dir(override)
         if found is not None:
             return Resolution(found, "machine", override)
diff --git a/tests/test_round40.py b/tests/test_round40.py
index f4e37a6..27a6c5d 100644
--- a/tests/test_round40.py
+++ b/tests/test_round40.py
@@ -241,6 +241,46 @@ class TestMusicFolderResolution:
         assert state.path == elsewhere
         assert state.source == "machine"
 
+    def test_the_pre_010_music_root_key_counts_as_an_override(
+            self, tmp_path, isolated_config):
+        """`--music-root … --save-config` has always written this machine's
+        media folder to config.json as `music_root`. Every library imported that
+        way already knows where its music is here, so a machine that mounts the
+        drive at a different path must not be asked to go find it."""
+        from lintunes.config import save_config
+        media = tmp_path / "media"
+        media.mkdir()
+        save_config({"music_root": str(media)})
+
+        # The shared value is another machine's mount point, unreachable here.
+        gone = Library(music_folder="/run/media/trav/tummult/music/iTunes Media")
+        state = music_folder.resolve(gone, tmp_path)
+
+        assert state.path == media
+        assert state.source == "machine"
+
+    def test_the_newer_override_key_still_wins(self, tmp_path, isolated_config):
+        from lintunes.config import save_config
+        chosen, imported = tmp_path / "chosen", tmp_path / "imported"
+        chosen.mkdir()
+        imported.mkdir()
+        save_config({"music_folder_override": str(chosen),
+                     "music_root": str(imported)})
+
+        state = music_folder.resolve(Library(music_folder="/nope"), tmp_path)
+
+        assert state.path == chosen
+
+    def test_a_stale_music_root_does_not_resolve(self, tmp_path, isolated_config):
+        """It's still a candidate, not an answer — the folder has to be there."""
+        from lintunes.config import save_config
+        save_config({"music_root": str(tmp_path / "unplugged")})
+
+        state = music_folder.resolve(Library(music_folder="/nope"), tmp_path)
+
+        assert state.path is None
+        assert state.source == "missing"
+
     def test_unset_and_missing_are_different_conversations(self, tmp_path,
                                                            isolated_config):
         assert music_folder.resolve(Library(), tmp_path).source == "unset"