diff --git a/YACReaderLibrary/server/controllers/v2/comiccontroller_v2.cpp b/YACReaderLibrary/server/controllers/v2/comiccontroller_v2.cpp
index 02ecc249..9a43a6a2 100644
--- a/YACReaderLibrary/server/controllers/v2/comiccontroller_v2.cpp
+++ b/YACReaderLibrary/server/controllers/v2/comiccontroller_v2.cpp
@@ -17,10 +17,16 @@
 ComicControllerV2::ComicControllerV2() {}
 
 void ComicControllerV2::service(HttpRequest& request, HttpResponse& response)
-{
-	HttpSession session=Static::sessionStore->getSession(request,response,false);
-    YACReaderHttpSession *ySession = Static::yacreaderSessionStore->getYACReaderSessionHttpSession(session.getId());
-
+{
+    QByteArray token = request.getHeader("x-request-id");
+    YACReaderHttpSession *ySession = Static::yacreaderSessionStore->getYACReaderSessionHttpSession(token);
+    
+    if (ySession == nullptr) {
+        response.setStatus(404,"not found");
+        response.write("404 not found",true);
+        return;
+    }
+    
     QString path = QUrl::fromPercentEncoding(request.getPath()).toUtf8();
 	QStringList pathElements = path.split('/');
     qulonglong libraryId = pathElements.at(3).toLongLong();
@@ -45,9 +51,6 @@ void ComicControllerV2::service(HttpRequest& request, HttpResponse& response)
 	
     ComicDB comic = DBHelper::getComicInfo(libraryId, comicId);
 
-    if(!remoteComic)
-        ySession->setDownloadedComic(comic.info.hash);
-
     Comic * comicFile = FactoryComic::newComic(libraries.getPath(libraryId)+comic.path);
 
 	if(comicFile != NULL)
diff --git a/YACReaderLibrary/server/controllers/v2/covercontroller_v2.cpp b/YACReaderLibrary/server/controllers/v2/covercontroller_v2.cpp
index e83c65ef..da6a2001 100644
--- a/YACReaderLibrary/server/controllers/v2/covercontroller_v2.cpp
+++ b/YACReaderLibrary/server/controllers/v2/covercontroller_v2.cpp
@@ -10,9 +10,6 @@ CoverControllerV2::CoverControllerV2() {}
 
 void CoverControllerV2::service(HttpRequest& request, HttpResponse& response)
 {
-	HttpSession session=Static::sessionStore->getSession(request,response,false);
-    YACReaderHttpSession *ySession = Static::yacreaderSessionStore->getYACReaderSessionHttpSession(session.getId());
-
 	response.setHeader("Content-Type", "image/jpeg");
 	response.setHeader("Connection","close");
 	//response.setHeader("Content-Type", "plain/text; charset=ISO-8859-1");
@@ -24,8 +21,6 @@ void CoverControllerV2::service(HttpRequest& request, HttpResponse& response)
     QString libraryName = DBHelper::getLibraryName(pathElements.at(3).toInt());
     QString fileName = pathElements.at(5);
 
-    bool folderCover = request.getParameter("folderCover").length()>0;
-
 	//response.writeText(path+"<br/>");
 	//response.writeText(libraryName+"<br/>");
 	//response.writeText(libraries.value(libraryName)+"/.yacreaderlibrary/covers/"+fileName+"<br/>");
diff --git a/YACReaderLibrary/server/controllers/v2/librariescontroller_v2.cpp b/YACReaderLibrary/server/controllers/v2/librariescontroller_v2.cpp
index bd803e44..ac75f432 100644
--- a/YACReaderLibrary/server/controllers/v2/librariescontroller_v2.cpp
+++ b/YACReaderLibrary/server/controllers/v2/librariescontroller_v2.cpp
@@ -11,8 +11,6 @@ LibrariesControllerV2::LibrariesControllerV2() {}
 
 void LibrariesControllerV2::service(HttpRequest& request, HttpResponse& response)
 {
-    HttpSession session=Static::sessionStore->getSession(request,response,false);
-
     response.setHeader("Content-Type", "application/json");
     response.setHeader("Connection","close");
 
diff --git a/YACReaderLibrary/server/controllers/v2/pagecontroller_v2.cpp b/YACReaderLibrary/server/controllers/v2/pagecontroller_v2.cpp
index 668f352b..79279865 100644
--- a/YACReaderLibrary/server/controllers/v2/pagecontroller_v2.cpp
+++ b/YACReaderLibrary/server/controllers/v2/pagecontroller_v2.cpp
@@ -16,10 +16,16 @@
 PageControllerV2::PageControllerV2() {}
 
 void PageControllerV2::service(HttpRequest& request, HttpResponse& response)
-{
-	HttpSession session=Static::sessionStore->getSession(request,response,false);
-    YACReaderHttpSession *ySession = Static::yacreaderSessionStore->getYACReaderSessionHttpSession(session.getId());
-
+{
+    QByteArray token = request.getHeader("x-request-id");
+    YACReaderHttpSession *ySession = Static::yacreaderSessionStore->getYACReaderSessionHttpSession(token);
+    
+    if (ySession == nullptr) {
+        response.setStatus(404,"not found");
+        response.write("404 not found",true);
+        return;
+    }
+    
     QString path = QUrl::fromPercentEncoding(request.getPath()).toUtf8();
     bool remote = path.endsWith("remote");
 
diff --git a/YACReaderLibrary/server/controllers/v2/updatecomiccontroller_v2.cpp b/YACReaderLibrary/server/controllers/v2/updatecomiccontroller_v2.cpp
index a683f16e..df9d363f 100644
--- a/YACReaderLibrary/server/controllers/v2/updatecomiccontroller_v2.cpp
+++ b/YACReaderLibrary/server/controllers/v2/updatecomiccontroller_v2.cpp
@@ -15,8 +15,6 @@ UpdateComicControllerV2::UpdateComicControllerV2(){}
 
 void UpdateComicControllerV2::service(HttpRequest &request, HttpResponse &response)
 {
-    HttpSession session=Static::sessionStore->getSession(request,response,false);
-
     QString path = QUrl::fromPercentEncoding(request.getPath()).toUtf8();
     QStringList pathElements = path.split('/');
     qulonglong libraryId = pathElements.at(3).toULongLong();
diff --git a/YACReaderLibrary/server/lib/httpserver/staticfilecontroller.cpp b/YACReaderLibrary/server/lib/httpserver/staticfilecontroller.cpp
index dd940d3e..090580d4 100644
--- a/YACReaderLibrary/server/lib/httpserver/staticfilecontroller.cpp
+++ b/YACReaderLibrary/server/lib/httpserver/staticfilecontroller.cpp
@@ -68,9 +68,14 @@ void StaticFileController::service(HttpRequest& request, HttpResponse& response)
         QString fileName = paths.last();
         stringPath.remove(fileName);
         HttpSession session=Static::sessionStore->getSession(request,response,false);
-        YACReaderHttpSession *ySession = Static::yacreaderSessionStore->getYACReaderSessionHttpSession(session.getId());
-        QString device = ySession->getDeviceType();
-        QString display = ySession->getDisplayType();
+        YACReaderHttpSession *ySession = Static::yacreaderSessionStore->getYACReaderSessionHttpSession(session.getId());
+        QString device = "ipad";
+        QString display = "@2x";
+        if (ySession != nullptr) {
+            device = ySession->getDeviceType();
+            display = ySession->getDisplayType();
+        }
+        
         if(fileName.endsWith(".png"))
             fileName = getDeviceAwareFileName(fileName, device, display, request.getHeader("Accept-Language"), stringPath);
         else
diff --git a/YACReaderLibrary/server/requestmapper.cpp b/YACReaderLibrary/server/requestmapper.cpp
index 8bc9f912..f38d77f1 100644
--- a/YACReaderLibrary/server/requestmapper.cpp
+++ b/YACReaderLibrary/server/requestmapper.cpp
@@ -44,12 +44,17 @@
 #include "yacreader_http_session.h"
 
 #include "QsLog.h"
+
+QMutex RequestMapper::mutex;
+
 
 RequestMapper::RequestMapper(QObject* parent)
 	:HttpRequestHandler(parent) {}
 
-void RequestMapper::loadSession(HttpRequest & request, HttpResponse& response)
-{
+void RequestMapper::loadSessionV1(HttpRequest & request, HttpResponse& response)
+{
+    QMutexLocker locker(&mutex);
+    
     HttpSession session=Static::sessionStore->getSession(request,response);
     if(session.contains("ySession")) //session is already alive check if it is needed to update comics
     {
@@ -112,11 +117,33 @@ void RequestMapper::loadSession(HttpRequest & request, HttpResponse& response)
         }
 
     }
+}
+
+void RequestMapper::loadSessionV2(HttpRequest & request, HttpResponse& response)
+{
+    QMutexLocker locker(&mutex);
+    
+    QByteArray token = request.getHeader("x-request-id");
+    
+    if (token.isEmpty()) {
+        return;
+    }
+    
+    YACReaderHttpSession *yRecoveredSession = Static::yacreaderSessionStore->getYACReaderSessionHttpSession(token);
+    
+    if(yRecoveredSession == nullptr) //session is already alive check if it is needed to update comics
+    {
+        YACReaderHttpSession *ySession = new YACReaderHttpSession(this);
+        
+        Static::yacreaderSessionStore->addYACReaderHttpSession(token, ySession);
+    }
 }
 
 void RequestMapper::service(HttpRequest& request, HttpResponse& response) {
-    QByteArray path=request.getPath();
-    qDebug("RequestMapper: path=%s",path.data());
+    QByteArray path=request.getPath();
+    
+    QLOG_TRACE() << "RequestMapper: path=" << path.data();
+    QLOG_TRACE() << "X-Request-Id: " << request.getHeader("x-request-id");
 
     if (path.startsWith("/v2"))
     {
@@ -150,7 +177,7 @@ void RequestMapper::serviceV1(HttpRequest& request, HttpResponse& response)
     path = QUrl::fromPercentEncoding(path).toUtf8();
 
     if(!sync.exactMatch(path)) //no session is needed for syncback info, until security will be added
-        loadSession(request, response);
+        loadSessionV1(request, response);
 
     //primera petición, se ha hecho un post, se sirven las bibliotecas si la seguridad mediante login no está habilitada
     if(path == "/")  //Don't send data to the server using '/' !!!!
@@ -221,7 +248,7 @@ void RequestMapper::serviceV2(HttpRequest& request, HttpResponse& response)
     QRegExp comicDownloadInfo("/v2/library/.+/comic/[0-9]+/?"); //get comic info (basic/download info)
     QRegExp comicOpenForDownloading("/v2/library/.+/comic/[0-9]+/info/?"); //get comic info (full info + opening)
     QRegExp comicOpenForRemoteReading("/v2/library/.+/comic/[0-9]+/remote/?"); //the server will open for reading the comic
-    QRegExp comicFullInfo("/v2/library/.+/comic/[0-9]+/fullinfo/?"); //get comic info (full info + opening)
+    QRegExp comicFullInfo("/v2/library/.+/comic/[0-9]+/fullinfo/?"); //get comic info
     QRegExp comicUpdate("/v2/library/.+/comic/[0-9]+/update/?"); //get comic info
     QRegExp comicClose("/v2/library/.+/comic/[0-9]+/close/?"); //the server will close the comic and free memory
     QRegExp cover("/v2/library/.+/cover/[0-9a-f]+.jpg"); //get comic cover (navigation)
@@ -243,7 +270,7 @@ void RequestMapper::serviceV2(HttpRequest& request, HttpResponse& response)
     path = QUrl::fromPercentEncoding(path).toUtf8();
 
     if(!sync.exactMatch(path)) //no session is needed for syncback info, until security will be added
-        loadSession(request, response);
+        loadSessionV2(request, response);
 
     //primera petición, se ha hecho un post, se sirven las bibliotecas si la seguridad mediante login no está habilitada
     if(path == "/v2/libraries")  //Don't send data to the server using '/' !!!!
@@ -262,10 +289,6 @@ void RequestMapper::serviceV2(HttpRequest& request, HttpResponse& response)
         }
         else
         {
-            //se comprueba que la sesión sea la correcta con el fin de evitar accesos no autorizados
-            HttpSession session=Static::sessionStore->getSession(request,response,false);
-            if(!session.isNull() && session.contains("ySession"))
-            {
                 if(library.indexIn(path)!=-1 && DBHelper::getLibraries().contains(library.cap(1).toInt()) )
                 {
                     if (folderInfo.exactMatch(path))
@@ -328,11 +351,6 @@ void RequestMapper::serviceV2(HttpRequest& request, HttpResponse& response)
                     //response.writeText(library.cap(1));
                     Static::staticFileController->service(request, response);
                 }
-            }
-            else //acceso no autorizado, redirección
-            {
-                ErrorControllerV2(300).service(request,response);
-            }
         }
     }
 }
diff --git a/YACReaderLibrary/server/requestmapper.h b/YACReaderLibrary/server/requestmapper.h
index 6ab0f92e..4bccc45b 100644
--- a/YACReaderLibrary/server/requestmapper.h
+++ b/YACReaderLibrary/server/requestmapper.h
@@ -17,11 +17,14 @@ public:
     RequestMapper(QObject* parent=0);
 
     void service(HttpRequest& request, HttpResponse& response);
-    void loadSession(HttpRequest & request, HttpResponse& response);
+    void loadSessionV1(HttpRequest & request, HttpResponse& response);
+    void loadSessionV2(HttpRequest & request, HttpResponse& response);
 
 private:
     void serviceV1(HttpRequest& request, HttpResponse& response);
     void serviceV2(HttpRequest& request, HttpResponse& response);
+    
+    static QMutex mutex;
 };
 
 #endif // REQUESTMAPPER_H
diff --git a/YACReaderLibrary/server/yacreader_http_session_store.cpp b/YACReaderLibrary/server/yacreader_http_session_store.cpp
index 52a55bd3..df523f08 100644
--- a/YACReaderLibrary/server/yacreader_http_session_store.cpp
+++ b/YACReaderLibrary/server/yacreader_http_session_store.cpp
@@ -8,9 +8,11 @@
 
 YACReaderHttpSessionStore::YACReaderHttpSessionStore(HttpSessionStore *sessionStore, QObject *parent)
     : QObject(parent), sessionStore(sessionStore)
-{
-    connect(&cleanupTimer,SIGNAL(timeout()),this,SLOT(sessionTimerEvent()));
-    cleanupTimer.start(60000);
+{
+    //sessions are no longer http sessions in v2, we need another mechanism for cleaning
+
+    //connect(&cleanupTimer,SIGNAL(timeout()),this,SLOT(sessionTimerEvent()));
+    //cleanupTimer.start(60000);
 }
 
 void YACReaderHttpSessionStore::addYACReaderHttpSession(const QByteArray &httpSessionId, YACReaderHttpSession *yacreaderHttpSession)
@@ -28,8 +30,9 @@ YACReaderHttpSession *YACReaderHttpSessionStore::getYACReaderSessionHttpSession(
 }
 
 void YACReaderHttpSessionStore::sessionTimerEvent()
-{
-    QMutexLocker locker(&mutex);
+{
+    //sessions are no longer http sessions in v2, we are using a token, so sessionStore->getSession(id).isNull() is always true.
+    /*QMutexLocker locker(&mutex);
     for(const QByteArray &id : sessions.keys())
     {
         if(sessionStore->getSession(id).isNull())
@@ -40,5 +43,5 @@ void YACReaderHttpSessionStore::sessionTimerEvent()
 
             sessions.remove(id);
         }
-    }
+    }*/
 }