diff --git a/qutebrowser/browser/adblock.py b/qutebrowser/browser/adblock.py
index 20c096391..595234e80 100644
--- a/qutebrowser/browser/adblock.py
+++ b/qutebrowser/browser/adblock.py
@@ -116,7 +116,7 @@ class HostBlocker:
             self._local_hosts_file = None
         else:
             self._local_hosts_file = os.path.join(data_dir, 'blocked-hosts')
-            self.on_config_changed()
+        self.on_config_changed()
 
         config_dir = standarddir.config()
         if config_dir is None:
@@ -274,7 +274,7 @@ class HostBlocker:
     def on_config_changed(self):
         """Update files when the config changed."""
         urls = config.get('content', 'host-block-lists')
-        if urls is None:
+        if urls is None and self._local_hosts_file is not None:
             try:
                 os.remove(self._local_hosts_file)
             except FileNotFoundError:
diff --git a/tests/unit/browser/test_adblock.py b/tests/unit/browser/test_adblock.py
index 49605b4a6..06e638d3d 100644
--- a/tests/unit/browser/test_adblock.py
+++ b/tests/unit/browser/test_adblock.py
@@ -258,6 +258,9 @@ def test_without_datadir(config_stub, tmpdir, monkeypatch, win_registry):
     for str_url in URLS_TO_CHECK:
         assert not host_blocker.is_blocked(QUrl(str_url))
 
+    # To test on_config_changed
+    config_stub.set('content', 'host-block-lists', None)
+
 
 def test_disabled_blocking_update(basedir, config_stub, download_stub,
                                   data_tmpdir, tmpdir, win_registry):