diff --git a/src/resources/js/meet/app.js b/src/resources/js/meet/app.js
--- a/src/resources/js/meet/app.js
+++ b/src/resources/js/meet/app.js
@@ -85,9 +85,22 @@
     /**
      * Join the room session
      *
-     * @param data Session metadata and event handlers (token, shareToken, nickname, role, connections,
-     *             chatElement, menuElement, onDestroy, onJoinRequest, onDismiss, onConnectionChange,
-     *             onSessionDataUpdate, onMediaSetup)
+     * @param data Session metadata and event handlers:
+     *      token       - OpenVidu token for the main connection,
+     *      shareToken  - OpenVidu token for screen-sharing connection,
+     *      nickname    - Participant name,
+     *      role        - connection (participant) role(s),
+     *      connections - Optional metadata for other users connections (current state),
+     *      chatElement - DOM element for the chat widget,
+     *      menuElement - DOM element of the room toolbar,
+     *      onSuccess           - Callback for session connection (join) success
+     *      onError             - Callback for session connection (join) error
+     *      onDestroy           - Callback for session disconnection event,
+     *      onDismiss           - Callback for Dismiss action,
+     *      onJoinRequest       - Callback for join request,
+     *      onConnectionChange  - Callback for participant changes, e.g. role update,
+     *      onSessionDataUpdate - Callback for current user connection update,
+     *      onMediaSetup        - Called when user clicks the Media setup button
      */
     function joinRoom(data) {
         resize();
@@ -209,6 +222,10 @@
         // Connect with the token
         session.connect(data.token, data.params)
             .then(() => {
+                if (data.onSuccess) {
+                    data.onSuccess()
+                }
+
                 let params = {
                     connectionId: session.connection.connectionId,
                     role: data.role,
@@ -238,6 +255,10 @@
             })
             .catch(error => {
                 console.error('There was an error connecting to the session: ', error.message);
+
+                if (data.onError) {
+                    data.onError(error)
+                }
             })
 
         // Prepare the chat
diff --git a/src/resources/vue/Meet/Room.vue b/src/resources/vue/Meet/Room.vue
--- a/src/resources/vue/Meet/Room.vue
+++ b/src/resources/vue/Meet/Room.vue
@@ -226,13 +226,14 @@
                 roomState: 'init',
                 roomStateLabels: {
                     init: 'Checking the room...',
-                    404: 'The room does not exist.',
                     323: 'The room is closed. Please, wait for the owner to start the session.',
                     324: 'The room is closed. It will be open for others after you join.',
                     325: 'The room is ready. Please, provide a valid password.',
                     326: 'The room is locked. Please, enter your name and try again.',
                     327: 'Waiting for permission to join the room.',
-                    500: 'Failed to create a session. Server error.'
+                    404: 'The room does not exist.',
+                    429: 'Too many requests. Please, wait.',
+                    500: 'Failed to connect to the room. Server error.'
                 },
                 session: {}
             }
@@ -322,7 +323,7 @@
                             this.roomState = error.response.status
                         }
 
-                        button.prop('disabled', this.roomState == 'init' || this.roomState == 327 || this.roomState == 404)
+                        button.prop('disabled', this.roomState == 'init' || this.roomState == 327 || this.roomState >= 400)
 
                         if (data.config) {
                             this.session.config = data.config
@@ -359,6 +360,17 @@
                                 // Update room state every 10 seconds
                                 roomRequest = setTimeout(() => { this.initSession(true) }, 10000)
                                 break;
+
+                            case 429:
+                                // Rate limited, wait and try again
+                                const waitTime = error.response.headers['retry-after'] || 10
+                                roomRequest = setTimeout(() => { this.initSession(init) }, waitTime * 1000)
+                                break;
+
+                            default:
+                                if (this.roomState >= 400 && this.roomState != 404) {
+                                    this.roomState = 500
+                                }
                         }
                     })
 
@@ -437,24 +449,28 @@
                     return
                 }
 
-                if (this.roomState != 'ready') {
+                if (this.roomState != 'ready' && !this.session.token) {
                     this.initSession(true)
                     return
                 }
 
                 clearTimeout(roomRequest)
 
-                $('#app').addClass('meet')
-                $('#meet-setup').addClass('hidden')
-                $('#meet-session-toolbar,#meet-session-layout').removeClass('hidden')
-
-                if (!this.canShareScreen) {
-                    this.setMenuItem('screen', false, true)
-                }
-
                 this.session.nickname = this.nickname
                 this.session.menuElement = $('#meet-session-menu')[0]
                 this.session.chatElement = $('#meet-chat')[0]
+                this.session.onSuccess = () => {
+                    $('#app').addClass('meet')
+                    $('#meet-setup').addClass('hidden')
+                    $('#meet-session-toolbar,#meet-session-layout').removeClass('hidden')
+
+                    if (!this.canShareScreen) {
+                        this.setMenuItem('screen', false, true)
+                    }
+                }
+                this.session.onError = () => {
+                    this.roomState = 500
+                }
                 this.session.onDestroy = event => {
                     // TODO: Display different message for each reason: forceDisconnectByUser,
                     //       forceDisconnectByServer, sessionClosedByServer?