diff --git a/hobo/matomo/utils.py b/hobo/matomo/utils.py
index 8823728..1e2b638 100644
--- a/hobo/matomo/utils.py
+++ b/hobo/matomo/utils.py
@@ -25,6 +25,7 @@ from random import choice, randint
 from django.db import connection
 from django.conf import settings
 from django.core import exceptions
+from django.utils.encoding import force_bytes
 from django.utils.six.moves.urllib import parse as urlparse
 
 from hobo.environment.models import Variable, Wcs, Combo, Fargo
@@ -277,7 +278,7 @@ def upgrade_user(matomo, user_login, id_site):
     matomo.add_user(user_login, password, id_site)
 
     # build the user's login url
-    password_md5 = hashlib.md5(password).hexdigest()
+    password_md5 = hashlib.md5(force_bytes(password)).hexdigest()
     logme_url = '%s/index.php?module=Login&action=logme&login=%s&password=%s' % (
         matomo.url_ws_base, user_login, password_md5)
     return logme_url