diff --git a/onionshare/onion.py b/onionshare/onion.py
index 3e30761a..cf761bb9 100644
--- a/onionshare/onion.py
+++ b/onionshare/onion.py
@@ -445,7 +445,10 @@ class Onion(object):
                 self.auth_string = 'HidServAuth {} {}'.format(onion_host, auth_cookie)
 
         self.settings.save()
-        return onion_host
+        if onion_host is not None:
+            return onion_host
+        else:
+            raise TorErrorProtocolError(strings._('error_tor_protocol_error'))
 
     def cleanup(self, stop_tor=True):
         """