diff --git a/appservice.py b/appservice.py
index 62dee59..3c66a33 100644
--- a/appservice.py
+++ b/appservice.py
@@ -58,9 +58,11 @@ def query_alias(alias):
             room['name'] = channel_settings['name']
         if 'description' in channel_settings:
             room['topic'] = channel_settings['description']
-        if channel.acl.read.any_user:
+        if channel.acl.read.public:
             room['preset'] = 'public_chat'
             room['visibility'] = 'public'
+        else:
+            abort(401)
 
         url = app.config['MATRIX_HOST'] + '/_matrix/client/api/v1/createRoom?access_token='
         url += app.config['MATRIX_AS_TOKEN']
@@ -350,7 +352,7 @@ def get_channel_settings(channel_id):
 
     return channel_settings
 
-def create_room(channel, invite):
+def create_room(channel, user):
     channel_settings = {}
     for item in channel.raw:
         if item.type == 'io.pnut.core.chat-settings':
@@ -358,19 +360,21 @@ def create_room(channel, invite):
 
     # Matrix sdk doesn't include all details in a single call
     room = {'room_alias_name': app.config['MATRIX_PNUT_PREFIX'] + channel.id}
-    logger.debug(invite)
+    logger.debug(user)
     logger.debug(room)
-    room['invite'] = [invite]
+    room['invite'] = [user.matrix_id]
     if 'name' in channel_settings:
         room['name'] = channel_settings['name']
     if 'description' in channel_settings:
         room['topic'] = channel_settings['description']
-    if channel.acl.read.any_user:
+    if channel.acl.read.public:
         room['preset'] = 'public_chat'
         room['visibility'] = 'public'
-    else:
+    elif channel.acl.read.any_user or channel.acl.read.you:
         room['preset'] = 'private_chat'
         room['visibility'] = 'private'
+    else:
+        abort(401)
 
     url = app.config['MATRIX_HOST'] + '/_matrix/client/api/v1/createRoom?access_token='
     url += app.config['MATRIX_AS_TOKEN']
@@ -523,15 +527,15 @@ def cmd_admin_link(room_id, pnut_chan_id):
         logger.exception(errmsg)
         return errmsg
 
-def cmd_admin_unlink(id):
+def cmd_admin_unlink(rid):
     matrix_api = MatrixHttpApi(app.config['MATRIX_HOST'], 
         token=app.config['MATRIX_AS_TOKEN'])
     pnutpy.api.add_authorization_token(app.config['MATRIX_PNUT_TOKEN'])
 
-    if id.startswith('!'):
-        room = Rooms.query.filter(Rooms.room_id == id).one_or_none()
+    if rid.startswith('!'):
+        room = Rooms.query.filter(Rooms.room_id == rid).one_or_none()
     else:
-        room = Rooms.query.filter(Rooms.pnut_chan == id).one_or_none()
+        room = Rooms.query.filter(Rooms.pnut_chan == rid).one_or_none()
 
     if hasattr(room, 'portal'):
         if room.portal:
@@ -815,8 +819,14 @@ def cmd_user_join(sender=None, channel_id=None):
         else:
             pnutpy.api.add_authorization_token(user.pnut_user_token)
             channel, meta = pnutpy.api.get_channel(channel_id, include_raw=1)
-            create_room(channel, user.matrix_id)
-            reply = "is working?"
+            room = Rooms.query.filter(Rooms.pnut_chan == channel_id).one_or_none()
+            if room is None:
+                create_room(channel, user)
+            else:
+                matrix_api = MatrixHttpApi(app.config['MATRIX_HOST'],
+                    token=app.config['MATRIX_AS_TOKEN'])
+                matrix_api.invite_user(room.room_id, sender)
+            reply = "ok"
 
     except pnutpy.errors.PnutAuthAPIException as e:
         reply = "You are currently not authorized on pnut.io"