diff --git a/frappe/email/doctype/email_domain/email_domain.py b/frappe/email/doctype/email_domain/email_domain.py
index e800b839b9..c601bb1a09 100644
--- a/frappe/email/doctype/email_domain/email_domain.py
+++ b/frappe/email/doctype/email_domain/email_domain.py
@@ -6,7 +6,7 @@ from __future__ import unicode_literals
 import frappe
 from frappe import _
 from frappe.model.document import Document
-from frappe.utils import validate_email_address ,cint
+from frappe.utils import validate_email_address ,cint, cstr
 import imaplib,poplib,smtplib
 from frappe.email.utils import get_port
 
@@ -51,7 +51,7 @@ class EmailDomain(Document):
 			try:
 				if self.use_tls and not self.smtp_port:
 					self.smtp_port = 587
-				sess = smtplib.SMTP((self.smtp_server or "").encode('utf-8'), cint(self.smtp_port) or None)
+				sess = smtplib.SMTP(cstr(self.smtp_server or ""), cint(self.smtp_port) or None)
 				sess.quit()
 			except Exception:
 				frappe.throw(_("Outgoing email account not correct"))
diff --git a/frappe/email/smtp.py b/frappe/email/smtp.py
index c09f3f9cdd..9eb588576d 100644
--- a/frappe/email/smtp.py
+++ b/frappe/email/smtp.py
@@ -8,7 +8,7 @@ import smtplib
 import email.utils
 import _socket, sys
 from frappe import _
-from frappe.utils import cint, parse_addr
+from frappe.utils import cint, cstr, parse_addr
 
 def send(email, append_to=None, retry=1):
 	"""Deprecated: Send the message or add it to Outbox Email"""
@@ -202,7 +202,7 @@ class SMTPServer:
 			if self.use_tls and not self.port:
 				self.port = 587
 
-			self._sess = smtplib.SMTP((self.server or "").encode('utf-8'),
+			self._sess = smtplib.SMTP(cstr(self.server or ""),
 				cint(self.port) or None)
 
 			if not self._sess: