diff --git a/lix/libstore/local-store.cc b/lix/libstore/local-store.cc
index 4617649a2..f2d6dac7c 100644
--- a/lix/libstore/local-store.cc
+++ b/lix/libstore/local-store.cc
@@ -322,6 +322,12 @@ LocalStore::LocalStore(LocalStoreConfig config)
                 "which is no longer supported. To convert to the new format,\n"
                 "please use the original Nix version 1.11 first.");
 
+        if (curSchema < 7)
+            throw Error(
+                "Your Nix store may contain immutable inodes, "
+                "which is no longer supported. To convert to the new format "
+                "please run the original Lix version 2.92 first.");
+
         if (!tryLockFile(globalLock.get(), ltWrite)) {
             printInfo("waiting for exclusive access to the Nix store...");
             unlockFile(globalLock.get()); // We have acquired a shared lock; release it to prevent deadlocks
@@ -332,8 +338,6 @@ LocalStore::LocalStore(LocalStoreConfig config)
            have performed the upgrade already. */
         curSchema = getSchema();
 
-        if (curSchema < 7) { upgradeStore7(); }
-
         openDB(*state, false);
 
         if (curSchema < 8) {
@@ -1715,58 +1719,6 @@ std::optional<TrustedFlag> LocalStore::isTrustedClient()
 }
 
 
-#if defined(FS_IOC_SETFLAGS) && defined(FS_IOC_GETFLAGS) && defined(FS_IMMUTABLE_FL)
-
-static void makeMutable(const Path & path)
-{
-    checkInterrupt();
-
-    auto st = lstat(path);
-
-    if (!S_ISDIR(st.st_mode) && !S_ISREG(st.st_mode)) return;
-
-    if (S_ISDIR(st.st_mode)) {
-        for (auto & i : readDirectory(path))
-            makeMutable(path + "/" + i.name);
-    }
-
-    /* The O_NOFOLLOW is important to prevent us from changing the
-       mutable bit on the target of a symlink (which would be a
-       security hole). */
-    AutoCloseFD fd = open(path.c_str(), O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
-    if (fd == -1) {
-        if (errno == ELOOP) return; // it's a symlink
-        throw SysError("opening file '%1%'", path);
-    }
-
-    unsigned int flags = 0, old;
-
-    /* Silently ignore errors getting/setting the immutable flag so
-       that we work correctly on filesystems that don't support it. */
-    if (ioctl(fd, FS_IOC_GETFLAGS, &flags)) return;
-    old = flags;
-    flags &= ~FS_IMMUTABLE_FL;
-    if (old == flags) return;
-    if (ioctl(fd, FS_IOC_SETFLAGS, &flags)) return;
-}
-
-/* Upgrade from schema 6 (Nix 0.15) to schema 7 (Nix >= 1.3). */
-void LocalStore::upgradeStore7()
-{
-    if (getuid() != 0) return;
-    printInfo("removing immutable bits from the Nix store (this may take a while)...");
-    makeMutable(config_.realStoreDir);
-}
-
-#else
-
-void LocalStore::upgradeStore7()
-{
-}
-
-#endif
-
-
 void LocalStore::addSignatures(const StorePath & storePath, const StringSet & sigs)
 {
     retrySQLite([&]() {
diff --git a/lix/libstore/local-store.hh b/lix/libstore/local-store.hh
index 6c559b09c..f031edd8e 100644
--- a/lix/libstore/local-store.hh
+++ b/lix/libstore/local-store.hh
@@ -350,8 +350,6 @@ private:
 
     void updatePathInfo(DBState & state, const ValidPathInfo & info);
 
-    void upgradeStore6();
-    void upgradeStore7();
     PathSet queryValidPathsOld();
     ValidPathInfo queryPathInfoOld(const Path & path);