diff --git a/frappe/email/smtp.py b/frappe/email/smtp.py
index f53b835757..9ba81fa146 100644
--- a/frappe/email/smtp.py
+++ b/frappe/email/smtp.py
@@ -210,10 +210,9 @@ class SMTPServer:
 		try:
 			if self.use_ssl:
 				if not self.port:
-					self.smtp_port = 465
+					self.port = 465
 
-				self._sess = smtplib.SMTP_SSL((self.server or "").encode('utf-8'),
-						cint(self.port) or None)
+				self._sess = smtplib.SMTP_SSL((self.server or ""), cint(self.port))
 			else:
 				if self.use_tls and not self.port:
 					self.port = 587
diff --git a/frappe/email/test_smtp.py b/frappe/email/test_smtp.py
new file mode 100644
index 0000000000..869d708430
--- /dev/null
+++ b/frappe/email/test_smtp.py
@@ -0,0 +1,25 @@
+# Copyright (c) 2020, Frappe Technologies Pvt. Ltd. and Contributors
+# License: The MIT License
+
+import unittest
+from frappe.email.smtp import SMTPServer
+
+class TestSMTP(unittest.TestCase):
+	def test_smtp_ssl_session(self):
+		for port in [None, 0, 465, "465"]:
+			make_server(port, 1, 0)
+
+	def test_smtp_tls_session(self):
+		for port in [None, 0, 587, "587"]:
+			make_server(port, 0, 1)
+
+
+def make_server(port, ssl, tls):
+	server = SMTPServer(
+		server = "smtp.gmail.com",
+		port = port,
+		use_ssl = ssl,
+		use_tls = tls
+	)
+
+	server.sess
\ No newline at end of file