diff --git a/clientapp/models/me.js b/clientapp/models/me.js
index 7e5f24d..d662de4 100644
--- a/clientapp/models/me.js
+++ b/clientapp/models/me.js
@@ -199,7 +199,7 @@ module.exports = HumanModel.define({
     },
     registerDevice: function () {
         var deviceID = app.state.deviceID;
-        if (!!deviceID) {
+        if (!!deviceID && deviceID !== undefined && deviceID !== 'undefined') {
             client.otalkRegister(deviceID).then(function () {
                 client.registerPush('push@push.otalk.im/prod');
             }).catch(function (err) {
diff --git a/clientapp/models/state.js b/clientapp/models/state.js
index 9fec57a..da38f72 100644
--- a/clientapp/models/state.js
+++ b/clientapp/models/state.js
@@ -62,7 +62,7 @@ module.exports = HumanModel.define({
         deviceIDReady: {
             deps: ['connected', 'deviceID'],
             fn: function () {
-                return (this.connected && this.deviceID);
+                return (this.connected && !!this.deviceID);
             }
         }
     },
diff --git a/package.json b/package.json
index 5a0c5f2..9bf5ba8 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "otalk.im",
-    "version": "0.0.18",
+    "version": "0.0.19",
     "description": "Otalk: WebRTC Enabled XMPP Client, in the Browser",
     "repository": {
         "type": "git",