diff --git a/client/assets/css/reset.scss b/client/assets/css/reset.scss
index 2b9a27ae..9bb0e78c 100644
--- a/client/assets/css/reset.scss
+++ b/client/assets/css/reset.scss
@@ -13,6 +13,8 @@
     --super-light:  #f4f4f4;
     --error: #f26d6d;
     --success: #63d9b1;
+
+    --dark: #313538;
 }
 
 html {
diff --git a/client/components/breadcrumb.js b/client/components/breadcrumb.js
index c8249f17..55565edb 100644
--- a/client/components/breadcrumb.js
+++ b/client/components/breadcrumb.js
@@ -115,9 +115,15 @@ export class PathElementWrapper extends React.Component {
         super(props);
     }
 
-    limitSize(str){
-        if(str.length > 27){
-            return str.substring(0,20)+'...';
+    limitSize(str, is_highlight = false){
+        if(is_highlight === true){
+            if(str.length > 30){
+                return str.substring(0,12).trim()+'...'+str.substring(str.length - 10, str.length).trim();
+            }
+        }else{
+            if(str.length > 27){
+                return str.substring(0,20).trim()+'...';
+            }
         }
         return str;
     }
@@ -135,7 +141,7 @@ export class PathElementWrapper extends React.Component {
                   <NgIf cond={this.props.path.minify === true}>
                     ...
                     <span className="title">
-                      {this.limitSize(this.props.path.label)}
+                      {this.limitSize(this.props.path.label, true)}
                     </span>
                   </NgIf>
                 </Link>
diff --git a/client/components/breadcrumb.scss b/client/components/breadcrumb.scss
index 1a6560ad..a52dca2a 100644
--- a/client/components/breadcrumb.scss
+++ b/client/components/breadcrumb.scss
@@ -39,10 +39,12 @@
         display: inline-block;
         .label{color: var(--color);padding: 2px 5px;}
         a.label{
+            position: relative;
             color: var(--light);
             span.title{
                 position: absolute;
-                background: var(--color);
+                left: 0;
+                background: var(--dark);
                 color: white;
                 font-size: 0.8em;
                 opacity: 0;
@@ -50,7 +52,7 @@
                 border-radius: 2px;
                 white-space: nowrap;
                 padding: 3px 10px!important;
-                margin: 5px 0px 5px -5px;
+                margin: 25px 0px 5px 0px;
             }
         }
 
diff --git a/client/helpers/ajax.js b/client/helpers/ajax.js
index 033b3381..c0b59ca5 100644
--- a/client/helpers/ajax.js
+++ b/client/helpers/ajax.js
@@ -10,8 +10,6 @@ export function http_get(url, type = 'json'){
                             let data = JSON.parse(xhr.responseText);
                             if(data.status === 'ok'){
                                 done(data);
-                            }else if(data.status === 'redirect'){
-                                if(data.to === 'logout'){location.pathname = "/logout";}
                             }else{
                                 err(data);
                             }
@@ -22,11 +20,7 @@ export function http_get(url, type = 'json'){
                         done(xhr.responseText);
                     }
                 }else{
-                    if(navigator.onLine === false){
-                        err({status: xhr.status, code: "CONNECTION_LOST", message: 'Ooups! Looks like your internet has gone away'});
-                    }else{
-                        err({status: xhr.status, message: xhr.responseText || 'Oups! Something went wrong'});
-                    }
+                    handle_error_response(xhr, err);
                 }
             }
         }
@@ -52,8 +46,6 @@ export function http_post(url, data, type = 'json'){
                         let data = JSON.parse(xhr.responseText);
                         if(data.status === 'ok'){
                             done(data);
-                        }else if(data.status === 'redirect'){
-                            if(data.to === 'logout'){location.pathname = "/logout";}
                         }else{
                             err(data);
                         }
@@ -61,11 +53,7 @@ export function http_post(url, data, type = 'json'){
                         err({message: 'oups', trace: error});
                     }
                 }else{
-                    if(navigator.onLine === false){
-                        err({status: xhr.status, code: "CONNECTION_LOST", message: 'Connection Lost'});
-                    }else{
-                        err({status: xhr.status, message: xhr.responseText || 'Oups something went wrong'});
-                    }
+                    handle_error_response(xhr, err);
                 }
             }
         }
@@ -84,8 +72,6 @@ export function http_delete(url){
                         let data = JSON.parse(xhr.responseText);
                         if(data.status === 'ok'){
                             done(data);
-                        }else if(data.status === 'redirect'){
-                            if(data.to === 'logout'){location.pathname = "/logout";}
                         }else{
                             err(data);
                         }
@@ -93,14 +79,38 @@ export function http_delete(url){
                         err({message: 'oups', trace: error});
                     }
                 }else{
-                    if(navigator.onLine === false){
-                        err({status: xhr.status, code: "CONNECTION_LOST", message: 'Connection Lost'});
-                    }else{
-                        err({status: xhr.status, message: xhr.responseText || 'Oups something went wrong'});
-                    }
+                    handle_error_response(xhr, err);
                 }
             }
         }
         xhr.send(null);
     });
 }
+
+
+
+function handle_error_response(xhr, err){
+    let message = (function(content){
+        let message = content;
+        try{
+            message = JSON.parse(content)['message'];
+        }catch(err){}
+        return message;
+    })(xhr.responseText);
+
+    if(xhr.status === 500){
+        err({message: message || "Oups something went wrong with our servers"})
+    }else if(xhr.status === 401){
+        if(location.pathname !== '/login'){ location.pathname = "/login"; }
+        err({message: message || "Authentication error"});
+    }else if(xhr.status === 403){
+        err({message: message || "You can\'t do that"});
+    }else if(xhr.status === 413){
+        err({message: message || "Payload too large"});
+    }else if(navigator.onLine === false){
+        err({status: xhr.status, code: "CONNECTION_LOST", message: 'Connection Lost'});
+    }else{
+        err({status: xhr.status, message: xhr.responseText || 'Oups something went wrong'});
+    }
+
+}
diff --git a/client/model/session.js b/client/model/session.js
index a7ed29a6..d8130bfd 100644
--- a/client/model/session.js
+++ b/client/model/session.js
@@ -3,16 +3,19 @@ import { http_get, http_post, http_delete } from '../helpers/';
 class SessionManager{
     isLogged(){
         let url = '/api/session'
-        return http_get(url);
+        return http_get(url)
+            .then(data => data.result);
     }
 
     url(type){
         if(type === 'dropbox'){
             let url = '/api/session/auth/dropbox';
-            return http_get(url);
+            return http_get(url)
+                .then(data => data.result);
         }else if(type === 'gdrive'){
             let url = '/api/session/auth/gdrive';
-            return http_get(url);
+            return http_get(url)
+                .then(data => data.result);
         }else{
             return Promise.error({message: 'not authorization backend for: '+type, code: 'UNKNOWN_PROVIDER'})
         }
@@ -20,12 +23,14 @@ class SessionManager{
 
     authenticate(params){
         let url = '/api/session';
-        return http_post(url, params);
+        return http_post(url, params)
+            .then(data => data.result);
     }
 
     logout(){
         let url = '/api/session';
-        return http_delete(url);
+        return http_delete(url)
+            .then(data => data.result);
     }
 }
 
diff --git a/client/pages/viewerpage/ide.js b/client/pages/viewerpage/ide.js
index ff8c104f..f81f12b9 100644
--- a/client/pages/viewerpage/ide.js
+++ b/client/pages/viewerpage/ide.js
@@ -40,7 +40,7 @@ export class IDE extends React.Component {
               <MenuBar title={this.props.filename} download={this.props.url} />
               <Editor onSave={this.save.bind(this)} filename={this.props.filename} content={this.props.content} onChange={this.onContentUpdate.bind(this)} />
 
-              <ReactCSSTransitionGroup transitionName="fab" transitionLeave={true} transitionEnter={true} transitionAppear={true} transitionAppearTimeout="300" transitonEnterTimeout="300" transitionLeaveTimeout="200">
+              <ReactCSSTransitionGroup transitionName="fab" transitionLeave={true} transitionEnter={true} transitionAppear={true} transitionAppearTimeout={300} transitionEnterTimeout={300} transitionLeaveTimeout={200}>
                 <NgIf key={this.state.needSaving} cond={this.state.needSaving}>
                   <NgIf cond={!this.props.isSaving}>
                     <Fab onClick={this.save.bind(this)}><Icon name="save" style={{height: '100%', width: '100%'}}/></Fab>
diff --git a/client/pages/viewerpage/menubar.scss b/client/pages/viewerpage/menubar.scss
index 0b1b7b59..620370d4 100644
--- a/client/pages/viewerpage/menubar.scss
+++ b/client/pages/viewerpage/menubar.scss
@@ -1,5 +1,5 @@
 .component_menubar{
-    background: #313538;
+    background: var(--dark);
     color: #f1f1f1;
     border-bottom: 1px solid var(--color);
 
diff --git a/config_server.js b/config_server.js
index ad1a14a9..b0874bbb 100644
--- a/config_server.js
+++ b/config_server.js
@@ -22,5 +22,5 @@ module.exports = {
         clientID: "dropbox_client_id",
         redirectURI: "application_url/login"
     },
-    secret_key: 'not_so_secret_key'
+    secret_key: process.env.SECRET_KEY || 'not_so_secret_key'
 }
diff --git a/server/ctrl/files.js b/server/ctrl/files.js
index 73a87921..0286e6d4 100644
--- a/server/ctrl/files.js
+++ b/server/ctrl/files.js
@@ -11,7 +11,7 @@ app.use(function(req, res, next){
     if(req.cookies.auth !== null){
         return next();
     }else{
-        return res.send({status: 'redirect', to: 'logout'});
+        return res.status(401).send({status: "error", message: "You need to authenticate first"});
     }
 });
 
diff --git a/server/ctrl/session.js b/server/ctrl/session.js
index 01da8952..966293d2 100644
--- a/server/ctrl/session.js
+++ b/server/ctrl/session.js
@@ -24,7 +24,7 @@ app.post('/', function(req, res){
             };
             const cookie = crypto.encrypt(persist);
             if(Buffer.byteLength(cookie, 'utf-8') > 4096){
-                res.send({status: 'error', message: 'we can\'t authenticate you', })
+                res.status(413).send({status: 'error', message: 'we can\'t authenticate you', })
             }else{
                 res.cookie('auth', crypto.encrypt(persist), { maxAge: 365*24*60*60*1000, httpOnly: true, path: "/api/" });
                 res.send({status: 'ok'});
@@ -38,7 +38,7 @@ app.post('/', function(req, res){
                 }
                 return t;
             }
-            res.send({status: 'error', message: message(err), code: err.code});
+            res.status(401).send({status: 'error', message: message(err), code: err.code});
         });
 });
 
@@ -48,16 +48,16 @@ app.delete('/', function(req, res){
     // TODO in May 2019: remove the line below which was inserted to mitigate a cookie migration issue.
     res.clearCookie("auth"); // the issue was a change in the cookie path which would have make
                              // impossible for an existing user to logout
-    res.send({status: 'ok'})
+    res.send({status: 'ok'});
 });
 
 app.get('/auth/:id', function(req, res){
     Session.auth({type: req.params.id})
         .then((url) => {
-            res.send({status: 'ok', result: url})
+            res.send({status: 'ok', result: url});
         })
         .catch((err) => {
-            res.send({status: 'error', message: 'can\'t get authorization url', trace: err})
+            res.status(404).send({status: 'error', message: 'can\'t get authorization url', trace: err});
         });
 });
 
diff --git a/server/utils/crypto.js b/server/utils/crypto.js
index 4a74cb2b..e2837f8c 100644
--- a/server/utils/crypto.js
+++ b/server/utils/crypto.js
@@ -1,6 +1,6 @@
 const crypto = require('crypto'),
-    algorithm = 'aes-256-cbc',
-    password = require('../../config_server')['secret_key'];
+      algorithm = 'aes-256-cbc',
+      password = require('../../config_server')['secret_key'];
 
 module.exports = {
     encrypt: function(obj){