Thread does not do anything - c++

Question

I try to use a thread to tell the user the COM port for serial communication he entered was wrong. I have a thread class which tries to establish the connection and a function in my main, that should tell the user.
The compiler does not complain, but my program never enters the function. Maybe anyone can spot the mistake I made.
main.cpp:
WindowsDgpsGUIFrame::WindowsDgpsGUIFrame(wxWindow* parent,wxWindowID id)
{
...
Bind(wxEVT_THREAD, &WindowsDgpsGUIFrame::onConnectionFailed, this, wxID_EXIT);
...
}
void WindowsDgpsGUIFrame::OnButtonStartClick(wxCommandEvent& event)
{
NavigationThread* navigationThread = new NavigationThread(this, m_usedVariables);
m_navigationThread = navigationThread;
wxThreadError err = m_navigationThread->Create();
if(err != wxTHREAD_NO_ERROR)
{
StaticStatusText->Enable();
StaticStatusText->SetLabel("Could not create NavigationThread.");
}
else{
StaticStatusText->SetLabel("Thread created");
}
err = m_navigationThread->Run();
if(err != wxTHREAD_NO_ERROR)
{
StaticStatusText->SetLabel("Could not run thread.");
}
}
void WindowsDgpsGUIFrame::onConnectionFailed(wxThreadEvent& event)
{
StaticConnectionText->SetLabel(event.GetString());
}
thread.cpp:
wxThread::ExitCode NavigationThread::Entry()
{
Serial serial;
int resultGnss = serial.Open(m_gnssPort, STANDARD_BAUDRATE);
wxThreadEvent event(wxEVT_THREAD, wxID_RETRY);
if(resultGnss != 0)
{
event.SetString("Connection to GNSS box not possible. Try with another COM port.");
m_parent->GetEventHandler()->AddPendingEvent(event);
}
else{
event.SetString("Connection successful");
m_parent->GetEventHandler()->AddPendingEvent(event);
}
return 0;
}
The thread gets created and starts running, but even though the event is thrown in the thread the program never reaches onConnectionFailed().