diff --git a/trytond/protocols/dispatcher.py b/trytond/protocols/dispatcher.py
index 3bb21c260e..de37e16fc7 100644
--- a/trytond/protocols/dispatcher.py
+++ b/trytond/protocols/dispatcher.py
@@ -232,7 +232,8 @@ def create(database_name, password, lang, admin_password):
                         cursor.limit_clause('SELECT id FROM ir_lang ' \
                         'WHERE code = %s', 1) + ')' \
                     'WHERE login <> \'root\'', (lang,))
-            admin_password = hashlib.sha1(admin_password).hexdigest()
+            admin_password = hashlib.sha1(admin_password.encode('utf-8'))\
+                .hexdigest()
             cursor.execute('UPDATE res_user ' \
                     'SET password = %s ' \
                     'WHERE login = \'admin\'', (admin_password,))
diff --git a/trytond/security.py b/trytond/security.py
index e50d9f871c..14729bcbce 100644
--- a/trytond/security.py
+++ b/trytond/security.py
@@ -18,7 +18,6 @@ def login(dbname, loginname, password, cache=True):
     with Transaction().start(dbname, 0) as transaction:
         pool = _get_pool(dbname)
         User = pool.get('res.user')
-        password = password.decode('utf-8')
         user_id = User.get_login(loginname, password)
         transaction.cursor.commit()
     if user_id: