diff --git a/gui/applicationdialog.cpp b/gui/applicationdialog.cpp
index 77d55ced1..97a73cd54 100644
--- a/gui/applicationdialog.cpp
+++ b/gui/applicationdialog.cpp
@@ -24,6 +24,7 @@
 #include <QLabel>
 #include <QFileDialog>
 #include <QDebug>
+#include <QMessageBox>
 
 
 ApplicationDialog::ApplicationDialog(const QString &name,
@@ -66,7 +67,7 @@ ApplicationDialog::ApplicationDialog(const QString &name,
 
     //Connect OK buttons
     connect(ok, SIGNAL(clicked()),
-            this, SLOT(accept()));
+            this, SLOT(Ok()));
     connect(cancel, SIGNAL(clicked()),
             this, SLOT(reject()));
     setLayout(layout);
@@ -105,3 +106,15 @@ QString ApplicationDialog::GetPath()
 {
     return mPath->text();
 }
+
+void ApplicationDialog::Ok()
+{
+    if (mName->text().isEmpty() || mPath->text().isEmpty()) {
+        QMessageBox msgBox;
+        msgBox.setText("You must specify a name and a path for the application!");
+        msgBox.exec();
+    } else {
+    accept();
+    }
+}
+
diff --git a/gui/applicationdialog.h b/gui/applicationdialog.h
index 027cba12d..7c32667d6 100644
--- a/gui/applicationdialog.h
+++ b/gui/applicationdialog.h
@@ -61,6 +61,7 @@ public:
     */
     QString GetPath();
 protected slots:
+    void Ok();
 
     /**
     * @brief Slot to browse for an application
diff --git a/gui/applicationlist.cpp b/gui/applicationlist.cpp
index ec51845c7..4accf7c47 100644
--- a/gui/applicationlist.cpp
+++ b/gui/applicationlist.cpp
@@ -100,6 +100,10 @@ void ApplicationList::SetApplicationType(const int index,
 
 void ApplicationList::AddApplicationType(const QString &name, const QString &path)
 {
+    if (name.isEmpty() || path.isEmpty()) {
+        return;
+    }
+
     ApplicationType type;
     type.Name = name;
     type.Path = path;
diff --git a/gui/checkthread.cpp b/gui/checkthread.cpp
index 1a4ecb5db..edc9943b1 100644
--- a/gui/checkthread.cpp
+++ b/gui/checkthread.cpp
@@ -23,7 +23,7 @@
 
 CheckThread::CheckThread(ThreadResult &result) :
         mResult(result),
-        mCppCheck(result)
+        mCppcheck(result)
 {
     //ctor
 }
@@ -35,7 +35,7 @@ CheckThread::~CheckThread()
 
 void CheckThread::Check(Settings settings)
 {
-    mCppCheck.settings(settings);
+    mCppcheck.settings(settings);
     start();
 }
 
@@ -47,9 +47,9 @@ void CheckThread::run()
     while (!file.isEmpty())
     {
         qDebug() << "Checking file" << file;
-        mCppCheck.addFile(file.toStdString());
-        mCppCheck.check();
-        mCppCheck.clearFiles();
+        mCppcheck.addFile(file.toStdString());
+        mCppcheck.check();
+        mCppcheck.clearFiles();
         emit FileChecked(file);
 
         file = mResult.GetNextFile();
diff --git a/gui/checkthread.h b/gui/checkthread.h
index 0f1c8e7c9..44b0f18e5 100644
--- a/gui/checkthread.h
+++ b/gui/checkthread.h
@@ -63,10 +63,10 @@ signals:
 protected:
     ThreadResult &mResult;
     /**
-    * @brief CppCheck itself
+    * @brief Cppcheck itself
     *
     */
-    CppCheck mCppCheck;
+    CppCheck mCppcheck;
 private:
 };
 
diff --git a/gui/mainwindow.cpp b/gui/mainwindow.cpp
index ef5dccefa..23f39600e 100644
--- a/gui/mainwindow.cpp
+++ b/gui/mainwindow.cpp
@@ -23,24 +23,26 @@
 #include <QMenu>
 #include <QDirIterator>
 #include <QMenuBar>
+#include <QMessageBox>
 #include "../src/filelister.h"
-
+#include "../src/cppcheckexecutor.h"
 
 MainWindow::MainWindow() :
-        mSettings(tr("CppCheck"), tr("CppCheck-GUI")),
+        mSettings(tr("Cppcheck"), tr("Cppcheck-GUI")),
         mActionExit(tr("E&xit"), this),
         mActionCheckFiles(tr("&Check files(s)"), this),
         mActionClearResults(tr("Clear &results"), this),
         mActionReCheck(tr("Recheck files"), this),
         mActionCheckDirectory(tr("Check &directory"), this),
         mActionSettings(tr("&Settings"), this),
-        mActionShowAll(tr("Show &more errors"), this),
+        mActionShowAll(tr("show possible false positives"), this),
         mActionShowSecurity(tr("Show &security errors"), this),
         mActionShowStyle(tr("Show s&tyle errors"), this),
         mActionShowUnused(tr("Show errors on &unused functions"), this),
         mActionShowErrors(tr("Show &common errors"), this),
         mActionShowCheckAll(tr("Check all"), this),
         mActionShowUncheckAll(tr("Uncheck all"), this),
+        mActionAbout(tr("About"), this),
         mResults(mSettings, mApplications)
 {
     QMenu *menu = menuBar()->addMenu(tr("&File"));
@@ -69,6 +71,9 @@ MainWindow::MainWindow() :
     QMenu *menuprogram = menuBar()->addMenu(tr("&Program"));
     menuprogram->addAction(&mActionSettings);
 
+    QMenu *menuHelp = menuBar()->addMenu(tr("&Help"));
+    menuHelp->addAction(&mActionAbout);
+
     setCentralWidget(&mResults);
 
 
@@ -87,10 +92,13 @@ MainWindow::MainWindow() :
     connect(&mActionShowUncheckAll, SIGNAL(triggered()), this, SLOT(UncheckAll()));
 
     connect(&mActionReCheck, SIGNAL(triggered()), this, SLOT(ReCheck()));
+
+    connect(&mActionAbout, SIGNAL(triggered()), this, SLOT(About()));
+
     connect(&mThread, SIGNAL(Done()), this, SLOT(CheckDone()));
     LoadSettings();
     mThread.Initialize(&mResults);
-    setWindowTitle(tr("CppCheck"));
+    setWindowTitle(tr("Cppcheck"));
 }
 
 MainWindow::~MainWindow()
@@ -161,7 +169,7 @@ void MainWindow::DoCheckFiles(QFileDialog::FileMode mode)
         mThread.SetFiles(RemoveUnacceptedFiles(fileNames));
         mSettings.setValue(tr("Check path"), dialog.directory().absolutePath());
         EnableCheckButtons(false);
-        mThread.Check(GetCppCheckSettings(), false);
+        mThread.Check(GetCppcheckSettings(), false);
     }
 }
 
@@ -175,7 +183,7 @@ void MainWindow::CheckDirectory()
     DoCheckFiles(QFileDialog::DirectoryOnly);
 }
 
-Settings MainWindow::GetCppCheckSettings()
+Settings MainWindow::GetCppcheckSettings()
 {
     Settings result;
     result._debug = false;
@@ -188,6 +196,11 @@ Settings MainWindow::GetCppCheckSettings()
     result._unusedFunctions = true;
     result._security = true;
     result._jobs = mSettings.value(tr("Check threads"), 1).toInt();
+
+    if (result._jobs <= 0) {
+        result._jobs = 1;
+    }
+
     return result;
 }
 
@@ -248,7 +261,7 @@ void MainWindow::ReCheck()
 {
     ClearResults();
     EnableCheckButtons(false);
-    mThread.Check(GetCppCheckSettings(), true);
+    mThread.Check(GetCppcheckSettings(), true);
 }
 
 void MainWindow::ClearResults()
@@ -316,3 +329,23 @@ void MainWindow::ToggleAllChecked(bool checked)
     mActionShowErrors.setChecked(checked);
     ShowErrors(checked);
 }
+
+void MainWindow::About()
+{
+    //TODO make a "GetVersionNumber" function to core cppcheck
+    CppCheckExecutor exec;
+    CppCheck check(exec);
+    const char *argv[] = {"","--version"};
+    QString version = check.parseFromArgs(2, argv).c_str();
+    version.replace("Cppcheck ","");
+
+        QMessageBox msgBox;
+        msgBox.setWindowTitle(tr("About..."));
+        msgBox.setText(QString("Cppcheck - A tool for static C/C++ code analysis.\nVersion %1\n\n" \
+                        "This program is licensed under the terms\n" \
+                        "of the GNU General Public License version 3\n" \
+                        "Available online under:\n" \
+                        "http://www.gnu.org/licenses/gpl-3.0.html\n\nSee AUTHORS file for the list of developers." \
+                        ).arg(version));
+        msgBox.exec();
+}
diff --git a/gui/mainwindow.h b/gui/mainwindow.h
index 587e3b807..aac0e676d 100644
--- a/gui/mainwindow.h
+++ b/gui/mainwindow.h
@@ -114,6 +114,12 @@ public slots:
     */
     void ProgramSettings();
 
+    /**
+    * @brief Slot to open program's about dialog
+    *
+    */
+    void About();
+
 protected slots:
 
     /**
@@ -155,7 +161,7 @@ protected:
     *
     * @return Default cppcheck settings
     */
-    Settings GetCppCheckSettings();
+    Settings GetCppcheckSettings();
 
     /**
     * @brief Removes all unaccepted (by cppcheck core) files from the list
@@ -262,6 +268,12 @@ protected:
     */
     QAction mActionShowUncheckAll;
 
+    /**
+    * @brief Action show about dialog
+    *
+    */
+    QAction mActionAbout;
+
 
 
     /**
diff --git a/gui/resultstree.cpp b/gui/resultstree.cpp
index f0556470e..c07bf8fcf 100644
--- a/gui/resultstree.cpp
+++ b/gui/resultstree.cpp
@@ -348,7 +348,7 @@ void ResultsTree::contextMenuEvent(QContextMenuEvent * e)
 
 void ResultsTree::StartApplication(QStandardItem *target, int application)
 {
-    if (target && application >= 0 && application < mApplications.GetApplicationCount())
+    if (target && application >= 0 && application < mApplications.GetApplicationCount() && target->parent())
     {
         QVariantMap data = target->data().toMap();
 
diff --git a/gui/settingsdialog.cpp b/gui/settingsdialog.cpp
index c9837c677..6d6f8cfc6 100644
--- a/gui/settingsdialog.cpp
+++ b/gui/settingsdialog.cpp
@@ -68,9 +68,13 @@ SettingsDialog::SettingsDialog(QSettings &programSettings, ApplicationList &list
     //Number of jobs
     QHBoxLayout *jobsLayout = new QHBoxLayout();
     mJobs = new QLineEdit(programSettings.value(tr("Check threads"), 1).toString());
+    mJobs->setValidator(new QIntValidator(1,9999,this));
+
     jobsLayout->addWidget(new QLabel(tr("Number of threads: ")));
     jobsLayout->addWidget(mJobs);
-    mJobs->setValidator(new QIntValidator(this));
+
+
+
     layout->addLayout(jobsLayout);
 
     //Force
@@ -169,7 +173,12 @@ void SettingsDialog::SaveSettings()
 
 void SettingsDialog::SaveCheckboxValues()
 {
-    mSettings.setValue(tr("Check threads"), mJobs->text().toInt());
+    int jobs = mJobs->text().toInt();
+    if (jobs <= 0) {
+        jobs = 1;
+    }
+
+    mSettings.setValue(tr("Check threads"), jobs);
     SaveCheckboxValue(mForce, tr("Check force"));
 }
 
@@ -197,7 +206,6 @@ void SettingsDialog::DeleteApplication()
 
     foreach(item, selected)
     {
-        qDebug() << item;
         mApplications.RemoveApplication(mListWidget->row(item));
         mListWidget->clear();
         PopulateListWidget();