diff --git a/core/admin/mailu/utils.py b/core/admin/mailu/utils.py
index f0a7fd20..4469ae8a 100644
--- a/core/admin/mailu/utils.py
+++ b/core/admin/mailu/utils.py
@@ -47,7 +47,7 @@ def handle_needs_login():
 
 # DNS stub configured to do DNSSEC enabled queries
 resolver = dns.resolver.Resolver()
-resolver.use_edns(0, 0, 1232)
+resolver.use_edns(0, dns.flags.DO, 1232)
 resolver.flags = dns.flags.AD | dns.flags.RD
 
 def has_dane_record(domain, timeout=10):
@@ -56,7 +56,6 @@ def has_dane_record(domain, timeout=10):
         if result.response.flags & dns.flags.AD:
             for record in result:
                 if isinstance(record, dns.rdtypes.ANY.TLSA.TLSA):
-                    record.validate()
                     if record.usage in [2,3] and record.selector in [0,1] and record.mtype in [0,1,2]:
                         return True
     except dns.resolver.NoNameservers:
diff --git a/core/admin/start.py b/core/admin/start.py
index 1964be5f..dd4f5b35 100755
--- a/core/admin/start.py
+++ b/core/admin/start.py
@@ -28,7 +28,7 @@ def test_DNS():
     import time
     # DNS stub configured to do DNSSEC enabled queries
     resolver = dns.resolver.Resolver()
-    resolver.use_edns(0, 0, 1232)
+    resolver.use_edns(0, dns.flags.DO, 1232)
     resolver.flags = dns.flags.AD | dns.flags.RD
     nameservers = resolver.nameservers
     for ns in nameservers: