diff --git a/src/calibre/library/prefs.py b/src/calibre/library/prefs.py
index 4bd39e20b2..1b80464d2a 100644
--- a/src/calibre/library/prefs.py
+++ b/src/calibre/library/prefs.py
@@ -84,13 +84,15 @@ class DBPrefs(dict):
         try:
             from_filename = os.path.join(library_path, 'metadata_db_prefs.json')
             with open(from_filename, "rb") as f:
+                self.clear()
                 d = json.load(f, object_hook=from_json)
                 self.db.conn.execute('DELETE FROM preferences')
                 for k,v in d.iteritems():
                     raw = self.to_raw(v)
                     self.db.conn.execute(
-                        'INSERT OR REPLACE INTO preferences (key,val) VALUES (?,?)',
-                        (k, raw))
+                        'INSERT INTO preferences (key,val) VALUES (?,?)', (k, raw))
+                self.db.conn.commit()
+                self.update(d)
         except:
             import traceback
             traceback.print_exc()
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