diff --git a/controle_cotisation/main.py b/controle_cotisation/main.py
index 3f8409b..7296a20 100755
--- a/controle_cotisation/main.py
+++ b/controle_cotisation/main.py
@@ -16,7 +16,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-import os, requests, json, datetime, shutil, quopri, subprocess
+import os, requests, json, datetime, shutil, quopri, subprocess, base64
 from requests.auth import HTTPBasicAuth
 from requests.auth import HTTPDigestAuth
 
@@ -105,7 +105,7 @@ def sendmail_with_attachment(headers, data, attachment_header, attachment, endin
     msg = bytes(headers + "\n", 'utf-8') \
         + quopri.encodestring(bytes(data, 'utf-8')) \
         + bytes(attachment_header + "\n", 'utf-8') \
-        + base64(attachment) \
+        + base64.b64encode(attachment) \
         + bytes(ending + "\n", 'utf-8')
 
     subprocess.run([SENDMAIL_LOCATION, "-t", "-oi"], input=msg)