diff --git a/RsyncUI.desktop b/RsyncUI.desktop
index 2ad07f2..db983d1 100644
--- a/RsyncUI.desktop
+++ b/RsyncUI.desktop
@@ -6,7 +6,7 @@ Comment=Client for rsync servers
 Comment[fr]=Client pour serveur rsync
 Version=1.0
 Exec=RsyncUI
-Icon=
+Icon=/usr/share/icons/RsyncUI.png
 Type=Application
 Terminal=false
 StartupNotify=true
diff --git a/RsyncUI.pro.user b/RsyncUI.pro.user
index 4c521a3..7d89b0c 100644
--- a/RsyncUI.pro.user
+++ b/RsyncUI.pro.user
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE QtCreatorProject>
-<!-- Written by QtCreator 4.14.2, 2023-02-10T14:36:52. -->
+<!-- Written by QtCreator 4.14.2, 2023-02-10T23:24:32. -->
 <qtcreator>
  <data>
   <variable>EnvironmentId</variable>
diff --git a/downloadfile.cpp b/downloadfile.cpp
index 8464ee2..e8edec5 100644
--- a/downloadfile.cpp
+++ b/downloadfile.cpp
@@ -96,6 +96,7 @@ void MainWindow::readRsyncOutput()
             );
 }*/
 
+// process raise error
 void MainWindow::downloadProcessStderr()
 {
     QByteArray errorLine;
diff --git a/main.cpp b/main.cpp
index ca39f1d..3b8944c 100644
--- a/main.cpp
+++ b/main.cpp
@@ -9,6 +9,7 @@ int main(int argc, char *argv[])
 
     QCoreApplication::setOrganizationName("RsyncUI");
     QCoreApplication::setApplicationName("RsyncUI");
+
     // Initialization of localization
     QLocale localeName = QLocale::system();
     QString localeFile = "/usr/share/locale/" + localeName.name()  + "/LC_MESSAGES/RsyncUI_" + localeName.name() + ".qm";
diff --git a/mainwindow.cpp b/mainwindow.cpp
index 1558e85..d5e67cf 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -40,10 +40,10 @@ MainWindow::MainWindow(QWidget *parent)
     QCoreApplication::setOrganizationName("RsyncUI");
     QCoreApplication::setApplicationName("RsyncUI");
 
-    // context menu for treewidget
+    // context menu for treewidget (list of files)
     ui->treeWidget->addAction(ui->actionDownload);
 
-    // init shortcut
+    // init configuration window
     config.setupUi(&Configuration);
 
     // init of About
@@ -57,12 +57,14 @@ MainWindow::MainWindow(QWidget *parent)
     connect(config.comboBox, QOverload<int>::of(&QComboBox::currentIndexChanged), this, &MainWindow::on_comboBox_currentIndexChanged);
 
     // init of widgets
-    ui->ktreewidgetsearchline->setTreeWidget(ui->treeWidget);
-    ui->ktreewidgetsearchline->setCaseSensitivity(Qt::CaseInsensitive);
-    ui->treeWidget->setHeaderLabels({tr("Path"), tr("Type"), tr("Size")} );
+    ui->ktreewidgetsearchline->setTreeWidget(ui->treeWidget);               // attach search widget to treewidget
+    ui->ktreewidgetsearchline->setCaseSensitivity(Qt::CaseInsensitive);     // and set it case insensitive
+    ui->treeWidget->setHeaderLabels({tr("Path"), tr("Type"), tr("Size")} ); // set header of columns of tree widget
 
+    // if last server exists in settings
     if (this->settings.contains("connexion/lastServer"))
     {
+        // set window to precedent server/port configuration
         ui->portEdit->setText(this->settings.value("connexion/port").toString());
         ui->khistorycombobox->setCurrentText(this->settings.value("connexion/lastServer").toString());
     }else
@@ -71,7 +73,7 @@ MainWindow::MainWindow(QWidget *parent)
         ui->khistorycombobox->clear();
     }
 
-    // setting arrowcursor for treeWidget, listWidget and listDownload
+    // setting arrowcursor for treeWidget, listWidget and listDownload to arrow
     ui->treeWidget->setCursor(Qt::ArrowCursor);
     ui->listWidget->setCursor(Qt::ArrowCursor);
     ui->listDownload->setCursor(Qt::ArrowCursor);
@@ -82,28 +84,32 @@ MainWindow::MainWindow(QWidget *parent)
     loadSettings();
 
     //setting configuration window
-    config.comboBox->setCurrentIndex(ui->toolBar->toolButtonStyle());
+    config.comboBox->setCurrentIndex(ui->toolBar->toolButtonStyle());       // setting combobox to saved settings
+
+    //setting unit of bandwidth limit
     config.UnitCombobox->addItems({tr("KB"), tr("MB"), tr("GB"), tr("TB"), tr("PB")});
 
+    //if exists list of donwloads in saved settings
     if (this->settings.value("Downloads/rows").toInt() != 0)
     {
-        //this->settings.endArray();
+        // asking if we load the list and continue downloading
         msgBox.setWindowTitle("RsyncUI");
         msgBox.setInformativeText(tr("A list of interrupted downloads exists, do you want to continue downloading ? if not the list will be cleared" ));
 
-        //QPushButton *remove = msgBox.addButton(tr("Remove"), QMessageBox::ActionRole);
         QPushButton *yes = msgBox.addButton(QMessageBox::Yes);
-
         msgBox.addButton(QMessageBox::No);
         msgBox.setDefaultButton(QMessageBox::Yes);
 
         msgBox.exec();
         reply = msgBox.clickedButton();
+
+        // if response is yes then loading list
         if(reply == yes)
         {
             loadDownloadList();
         }
     }
+    // load list of services
     populateList();
 }
 
@@ -112,11 +118,12 @@ MainWindow::~MainWindow()
     delete ui;
 }
 
-// Closing window has been clicked
+// Close window has been clicked
 void MainWindow::closeEvent (QCloseEvent *event)
 {
     QMessageBox::StandardButton reply;
     QMessageBox::StandardButtons param;
+    QString displayText;
 
     // saving settings
     saveSettings();
@@ -128,13 +135,15 @@ void MainWindow::closeEvent (QCloseEvent *event)
         if (config.autosaveCheckbox->checkState() != Qt::Checked)
         {
             param |= QMessageBox::Save;
+            displayText = tr("Clicking Save button, You can save the list of downloads\n");
         }
         reply = QMessageBox::question(
                 this,
                 "RsyncUI",
-                tr("Exiting will stop downloading, and will clear the download queue.\nYou can save the list of downloads\nDo you want to exit ?"),
+                tr("Exiting will stop downloading, and will clear the download queue.\nDo you want to exit ?") + displayText,
                 param,
                 QMessageBox::No);
+
         if (reply == QMessageBox::No)
         {
             // continuing
@@ -155,7 +164,6 @@ void MainWindow::closeEvent (QCloseEvent *event)
 // Populate treeview with list of files
 void MainWindow::populateTree(QTreeWidgetItem * parent)
 {
-    stringstream ss;
     QString path;
 
     // Clear treewidget
@@ -165,6 +173,7 @@ void MainWindow::populateTree(QTreeWidgetItem * parent)
         // setting cursor to "Wait"
         QGuiApplication::setOverrideCursor(Qt::WaitCursor);
 
+        // validating server's address
         if (validateServer(this->connexion.server))
         {
             // server is validated
@@ -179,8 +188,6 @@ void MainWindow::populateTree(QTreeWidgetItem * parent)
 // Populate Listview with list of services
 void MainWindow::populateList()
 {
-    //stringstream ss;
-    QString str;
     QString server;
     int port;
 
@@ -190,9 +197,11 @@ void MainWindow::populateList()
     {
         // clearing listwidget
         ui->listWidget->clear();
+
         this->connexion.server = server;
         this->connexion.port = port;
 
+        // setting cursor to "Wait"
         QGuiApplication::setOverrideCursor(Qt::WaitCursor);
 
         // verify if server is in history
@@ -203,6 +212,8 @@ void MainWindow::populateList()
             port = this->settings.value(server).toUInt();
             ui->portEdit->setText(QString::number(port));
             this->connexion.port = port;
+
+            //display list of services
             listServices();
         }else
         {
@@ -211,6 +222,7 @@ void MainWindow::populateList()
                 if (validateServer(server))
                 {
                     cout << server.toStdString() << endl;
+
                     // storing serverURL and port in settings
                     this->settings.setValue(server, port);
                     this->settings.sync();
@@ -219,14 +231,13 @@ void MainWindow::populateList()
                     // storing in history of combobox
                     ui->khistorycombobox->addToHistory(server);
 
-                    // "waiting" cursor
                     // load and display rsync services of the rsync server
                     listServices();
                 }
             }
         }
         this->settings.endGroup();
-        QGuiApplication::restoreOverrideCursor();  //setOverrideCursor(Qt::ArrowCursor);
+        QGuiApplication::restoreOverrideCursor();  //setting cursor to default
     }
 }
 
@@ -247,26 +258,32 @@ void MainWindow::listServices()
     myProcess = new QProcess(this);
     myProcess->start(cmd, param);
 
+    // waiting for response of the server with a timeout of 10 seconds
     while(myProcess->waitForReadyRead(10000))
     {
         while(!flag)
         {
             line = QString::fromUtf8(myProcess->readLine());
+            // line empty then buffer is empty so returning to wait new datas
             if (line.isEmpty())
             {
                 flag = true;
                 break;
             }
+            // extracting name and comment of the service
             v = line.split("\t");
             v[0].replace(" ", "");
             v[1].replace("\n", "");
             service = v[0] + "\n\t" + v[1];
 
+            // adding to list of services
             ui->listWidget->addItem(service);
         }
+        // buffer empty go to waiting new datas
         flag =false;
     }
 
+    // verifying error code
     testRsyncReturn(myProcess);
 }
 
@@ -276,10 +293,8 @@ void MainWindow::scanDir(QString server, int portN, QTreeWidgetItem *parent, QSt
     QString cmd;
     QStringList param;
     QString line;
-    QString errorRsync;
     QString size;
     QString filename;
-    QString dir;
     QTreeWidgetItem * item;
     QProcess * myProcess;
     bool isDir = false;
@@ -291,16 +306,19 @@ void MainWindow::scanDir(QString server, int portN, QTreeWidgetItem *parent, QSt
     myProcess = new QProcess(this);
     myProcess->start(cmd, param);
 
+    // waiting for response of the server with a timeout of 10 seconds
     while(myProcess->waitForReadyRead(100000))
     {
         while (!flag)
         {
             line = QString::fromUtf8(myProcess->readLine());
+            // line empty then buffer is empty so returning to wait new datas
             if (line.isEmpty())
             {
                 flag = true;
                 break;
             }
+            // extracting name, size and is dir/file
             line = line.simplified();
             size = line.section(" ", 1, 1);
             filename = line.section(" ", 4);
@@ -315,16 +333,19 @@ void MainWindow::scanDir(QString server, int portN, QTreeWidgetItem *parent, QSt
                 }
                 if (parent != NULL)
                 {
+                    //adding item to tree
                     item = addTreeChild(parent, filename, size, isDir);
                 }else
                 {
+                    //adding item to tree (as directory)
                     item = addTreeRoot(filename, size, isDir);
                 }
             }
         }
+
         flag = false;
     }
-
+    // buffer empty go to waiting new datas
     testRsyncReturn(myProcess);
 }
 
@@ -333,7 +354,6 @@ bool MainWindow::isIpAddress(QString server)
 {
     QStringList r;
     int elementN;
-    QString qr;
     bool ok;
 
     r = server.split('.');
@@ -360,9 +380,9 @@ bool MainWindow::validateServer(QString server)
     QString cmd;
     QStringList param;
     QString line;
-    QString errorDig;
     QProcess * myProcess;
     bool flag = false;
+    bool bflag = false;
 
     cmd = "dig";
     param << server;
@@ -370,23 +390,35 @@ bool MainWindow::validateServer(QString server)
     myProcess = new QProcess(this);
     myProcess->start(cmd, param);
 
+    // maiking a dig on the server's address
     while(myProcess->waitForReadyRead())
     {
-        line = QString::fromUtf8(myProcess->readAllStandardOutput());
-        if (line.indexOf(";; ANSWER SECTION:") != -1)
+        while (!bflag)
         {
-            flag = true;
+            line = QString::fromUtf8(myProcess->readAllStandardOutput());
+            // line empty then buffer is empty so returning to wait new datas
+            if (line.isEmpty())
+            {
+                bflag = true;
+                break;
+            }else if (line.indexOf(";; ANSWER SECTION:") != -1)
+            {
+                flag = true;
+            }
         }
+        bflag = false;
     }
 
     //testRsyncReturn(myProcess);
 
     if ( flag == false)
     {
+        //server's address is not valid testing if ip address is valid
         flag = isIpAddress(server);
     }
     if ( flag == false)
     {
+        // server-s address not valid
         QMessageBox::warning(
             this,
             "RsyncUI",
@@ -412,15 +444,15 @@ void MainWindow::on_connectButton_clicked()
 // add a dir in treeview
 QTreeWidgetItem * MainWindow::addTreeRoot(QString name, QString fileSize, bool isDir)
 {
-    // QTreeWidgetItem(QTreeWidget * parent, int type = Type)
     QTreeWidgetItem *treeItem = new QTreeWidgetItem(ui->treeWidget);
 
-    // QTreeWidgetItem::setText(int column, const QString & text)
     if (isDir == true)
     {
+        // item is a dir
         treeItem->setText(1, tr("Dir"));
     }else
     {
+        // item is a file
         treeItem->setText(1,tr("File"));
     }
     treeItem->setText(0, name);
@@ -432,15 +464,15 @@ QTreeWidgetItem * MainWindow::addTreeRoot(QString name, QString fileSize, bool i
 // add a file in treeview
 QTreeWidgetItem * MainWindow::addTreeChild(QTreeWidgetItem *parent, QString name, QString fileSize, bool isDir)
 {
-    // QTreeWidgetItem(QTreeWidget * parent, int type = Type)
     QTreeWidgetItem *treeItem = new QTreeWidgetItem();
 
-    // QTreeWidgetItem::setText(int column, const QString & text)
     if (isDir == true)
     {
+        // item is a dir
         treeItem->setText(1, tr("Dir"));
     }else
     {
+        // item is a file
         treeItem->setText(1,("File"));
     }
     treeItem->setText(0, name);
@@ -454,13 +486,14 @@ QTreeWidgetItem * MainWindow::addTreeChild(QTreeWidgetItem *parent, QString name
 // Slot acivated when a service in the list is clicked
 void MainWindow::on_listWidget_clicked()
 {
-    QString service;
     QString str;
 
     this->connexion.service = ui->listWidget->currentItem()->text().section("\n", 0 ,0);
     str = "Folder/" + this->connexion.server + "/" + this->connexion.service;
+    // if service exists in settings for this server
     if (this->settings.contains(str))
     {
+        // setting savePath from settings
         this->downloading.savePath = this->settings.value(str).toString();
     }
     populateTree(NULL);
@@ -477,17 +510,18 @@ void MainWindow::on_treeWidget_itemClicked(QTreeWidgetItem *item, bool downloadD
 
     itemR = item;
 
+    // assembling path from treewidget
     path = item->text(0);
     while(itemR->parent() != NULL)
     {
         itemR = itemR->parent();
-        path = itemR->text(0) + "/" + path;
+        // concatening parent to path
+        path.prepend(itemR->text(0) + "/");
     };
 
     if (item->text(1) == tr("File") or downloadDir == true)
     {
         // Item is a file
-
         if(ui->listDownload->findItems(path, Qt::MatchStartsWith).empty())
         {
             // exists saving path in settings ?
@@ -550,9 +584,10 @@ void MainWindow::stoppingDownload()
 void MainWindow::downloadFinished(int exitCode, QProcess::ExitStatus exitStatus)
 {
     QString path;
-    int pos;
     QString str;
+    int pos;
 
+    // test if process crashed
     if (exitStatus == QProcess::CrashExit)
     {
         QMessageBox::warning(
@@ -560,25 +595,36 @@ void MainWindow::downloadFinished(int exitCode, QProcess::ExitStatus exitStatus)
             "RsyncUI",
             tr("Rsync process crashed"));
     }
+    //test result code of command (if 20 then command stopped by user)
     if (exitCode != 0 and exitCode != 20)
     {
+        // displaying warning with exit code
         QMessageBox::warning(
             NULL,
             "RsyncUI",
             rsyncErrorStrings[exitCode]);
     }
 
+    // disconnecting signals to slots
     disconnect(this->downloading.process, 0, 0, 0);
+
+    // reset variables and window
     this->downloading.process= nullptr;
     ui->progressBar->hide();
     delete ui->listDownload->takeItem(0);
     this->downloading.clear();
+
+    // Some downloads staying in queue
     if (ui->listDownload->count() != 0)
     {
+        // autosave is activated
         if (config.autosaveCheckbox->checkState() == Qt::Checked)
         {
+            // saving download list
             saveDownloadList();
         }
+
+        // initializing download
         path = ui->listDownload->item(0)->text();
         pos = path.lastIndexOf("/");
         this->downloading.service = path.midRef(pos+1).toString();
@@ -587,12 +633,17 @@ void MainWindow::downloadFinished(int exitCode, QProcess::ExitStatus exitStatus)
         this->downloading.server = path.midRef(pos+4).toString();
         path.resize(pos);
         this->downloading.path = path;
+
+        // save path exists in settings ?
         str = "Folder/" + this->downloading.server + "/" + this->downloading.service;
         if (this->settings.contains(str))
         {
+            // setting savepath from saved settings
             this->downloading.savePath = this->settings.value(str).toString();
+            startDownloading();
         }else
         {
+            // no save path
             if(!on_DefaultSaveFolder_triggered())
             {
                 cout << "Error no save path so deleting download";
@@ -600,7 +651,6 @@ void MainWindow::downloadFinished(int exitCode, QProcess::ExitStatus exitStatus)
                 return;
             }
         }
-        startDownloading();
     }
 }
 
@@ -608,13 +658,12 @@ void MainWindow::downloadFinished(int exitCode, QProcess::ExitStatus exitStatus)
 // Slot activated when a line is clicked in queue list
 void MainWindow::on_listDownload_itemClicked(QListWidgetItem *item)
 {
-    QFileDialog dialog;
     QMessageBox::StandardButton reply;
 
-    //cout << item->text().toStdString() << endl;
     if (item->listWidget()->row(item) == 0)
     {
-       reply = QMessageBox::question(
+        // first line clicked on download list
+        reply = QMessageBox::question(
                 this,
                 "RsyncUI",
                 tr("Do you want to stop downloading and delete this file from download queue ?"),
@@ -622,10 +671,12 @@ void MainWindow::on_listDownload_itemClicked(QListWidgetItem *item)
                 QMessageBox::No);
         if (reply == QMessageBox::Yes)
         {
+            // stopping download
             emit (stopDownloading(this->downloading.process));
         }
     }else
     {
+        // not first line on download list
         reply = QMessageBox::question(
                 this,
                 "RsyncUI",
@@ -634,10 +685,12 @@ void MainWindow::on_listDownload_itemClicked(QListWidgetItem *item)
                 QMessageBox::No);
         if (reply == QMessageBox::Yes)
         {
+            // removing line from download list
             ui->listDownload->removeItemWidget(item);
             delete item;
             if (config.autosaveCheckbox->checkState() == Qt::Checked)
             {
+                // autosave acivated,so saving download list
                 saveDownloadList();
             }
         }
@@ -694,7 +747,6 @@ void MainWindow::saveSettings()
 // About
 void MainWindow::on_actionAbout_triggered()
 {
-    //TODO => initialisation
     QString text =  this->about.description + "\n\n" +
                     tr("Version") + ":     " + this->about.version + "\n" +
                     tr("Licence") + ":     " + this->about.licence + "\n" +
@@ -717,20 +769,24 @@ bool MainWindow::on_DefaultSaveFolder_triggered()
      QString folder;
      QString path;
 
+     // if service not selected display a message
      if (this->connexion.service.isEmpty())
      {
-         QMessageBox::warning(
-                 NULL,
-                 "RsyncUI",
-                 tr("Since the save path is linked to service, you need to select a service before you can select a folder"));
-                 return false;
+        QMessageBox::warning(
+                NULL,
+                "RsyncUI",
+                tr("Since the save path is linked to service, you need to select a service before you can select a folder"));
+                return false;
      }
+
+     // Asking for directory to save files
      path =  dialog.getExistingDirectory(this, tr("Choose folder where to save file"), QDir::homePath(), QFileDialog::ShowDirsOnly | QFileDialog::DontResolveSymlinks);
      if (!path.isEmpty())
      {
         this->downloading.savePath = path;
         if (!this->connexion.service.isEmpty() and !this->connexion.server.isEmpty())
         {
+            // saving save path in settings
             folder = "Folder/" + this->connexion.server + "/" + this->connexion.service;
             this->settings.setValue(folder, this->downloading.savePath);
             this->settings.sync();
@@ -759,6 +815,7 @@ void MainWindow::on_buttonBox_accepted()
     bw = config.spinBox->text();
     if (bw.toInt() == 0)
     {
+        // bandwidth = 0
         this->connexion.bandwidthLimit = 0;
         this->connexion.bandwidthLimitUnit = 0;
     }else
@@ -780,9 +837,11 @@ void MainWindow::saveDownloadList()
 {
     int nRows;
 
+    // remove list of downloads
     this->settings.remove("Downloads/");
+
+    // Saving list of current downloads
     nRows = ui->listDownload->count();
-    //this->settings.beginWriteArray("Downloads/");
     this->settings.beginGroup("Downloads");
     this->settings.setValue("rows", nRows);
     for (int i = 0; i < nRows; i++)
@@ -793,12 +852,14 @@ void MainWindow::saveDownloadList()
     this->settings.sync();
 }
 
+// Loading download list
 void MainWindow::loadDownloadList()
 {
     QString path;
     QString str;
     int pos;
 
+    this->settings.sync();
     this->settings.beginGroup("Downloads");
     int size = this->settings.value("rows").toInt();
     for (int i = 0; i < size; ++i)
@@ -807,8 +868,6 @@ void MainWindow::loadDownloadList()
     }
     this->settings.endGroup();
 
-    this->settings.sync();
-
     path = ui->listDownload->item(0)->text();
     pos = path.lastIndexOf("/");
     this->downloading.service = path.midRef(pos+1).toString();
@@ -825,6 +884,7 @@ void MainWindow::loadDownloadList()
     startDownloading();
 }
 
+// clear object downloading
 void Downloading::clear()
 {
     this->path.clear();
@@ -833,6 +893,7 @@ void Downloading::clear()
     this->service.clear();
 }
 
+// Context menu of file list clicked
 void MainWindow::on_actionDownload_triggered()
 {
     // action made in qt-designer and added in init function.
@@ -852,6 +913,7 @@ void MainWindow::on_actionDownload_triggered()
 }
 */
 
+// Chnage toolbar style
 void MainWindow::on_comboBox_currentIndexChanged(int index)
 {
     ui->toolBar->setToolButtonStyle((Qt::ToolButtonStyle)index);
diff --git a/tools.cpp b/tools.cpp
index b0cd9e6..2eb3d32 100644
--- a/tools.cpp
+++ b/tools.cpp
@@ -43,6 +43,7 @@ const vector<string> explode(const string& s, const char& c, int n = 0)
     return v;
 }
 
+// test return code of rsync
 bool testRsyncReturn(QProcess * myProcess)
 {
     if (myProcess->exitStatus() != 0)