diff --git a/src/phishing/smtp/client/smtp_web.py b/src/phishing/smtp/client/smtp_web.py
index 1ac2cca7a..75a99c8a3 100644
--- a/src/phishing/smtp/client/smtp_web.py
+++ b/src/phishing/smtp/client/smtp_web.py
@@ -479,7 +479,7 @@ def mail(to, subject, prioflag1, prioflag2, text):
     # if we specify to track users, this will replace the INSERTUSERHERE with
     # the "TO" field.
     if track_email.lower() == "on":
-        body_new = body_new.replace("INSERTUSERHERE", base64.b64encode(to.encode()))
+        body_new = body_new.replace("INSERTUSERHERE", str(base64.b64encode(to.encode())))
     # call the function to send email
     try:
         mail(to, subject, prioflag1, prioflag2, body_new)