diff --git a/wo/cli/plugins/site_functions.py b/wo/cli/plugins/site_functions.py
index 2afa650..e18f446 100644
--- a/wo/cli/plugins/site_functions.py
+++ b/wo/cli/plugins/site_functions.py
@@ -1486,7 +1486,7 @@ def checkWildcardExist(self, wo_domain_name):
     # define new csv dialect
     csv.register_dialect('acmeconf', delimiter='|')
     # open file
-    certfile = open('/var/lib/wo/cert.csv', 'rt')
+    certfile = open('/var/lib/wo/cert.csv', mode='rt', encoding='utf-8')
     reader = csv.reader(certfile, 'acmeconf')
     wo_wildcard_domain = ("*.{0}".format(wo_domain_name))
     for row in reader:
diff --git a/wo/core/domainvalidate.py b/wo/core/domainvalidate.py
index 574f6bc..36b8af0 100644
--- a/wo/core/domainvalidate.py
+++ b/wo/core/domainvalidate.py
@@ -32,10 +32,11 @@ def GetDomainlevel(domain):
     domain_name = domain.split('.')
     if domain_name[0] == 'www':
         domain_name = domain_name[1:]
+    domain_type = ''
     if os.path.isfile("/var/lib/wo/public_suffix_list.dat"):
         # Read mode opens a file for reading only.
         Suffix_file = open(
-            "/var/lib/wo/public_suffix_list.dat", "r")
+            "/var/lib/wo/public_suffix_list.dat", mode='rt', encoding='utf-8')
         # Read all the lines into a list.
         for domain_suffix in Suffix_file:
             if (str(domain_suffix).strip()) == ('.'.join(domain_name[1:])):