diff --git a/src/generatorthread.cpp b/src/generatorthread.cpp
--- a/src/generatorthread.cpp
+++ b/src/generatorthread.cpp
@@ -43,16 +43,19 @@
 
 void GeneratorThread::run()
 { 
-    Cirkuit::Backend* bestBackend = Backend::autoChooseBackend(m_doc);
     if (CirkuitSettings::autoSelectBackend()) {
-        if (bestBackend->id() != m_backend->id()) {
-            m_backend = bestBackend;
-            emit backendChanged(m_backend->name());
+        Cirkuit::Backend* bestBackend = Backend::autoChooseBackend(m_doc);
+        if (nullptr != bestBackend) {
+            if ((nullptr == m_backend) || (bestBackend->id() != m_backend->id())) {
+                m_backend = bestBackend;
+                emit backendChanged(m_backend->name());
+            }
         }
     }
-    
-    if (!m_backend) {
+
+    if (nullptr == m_backend) {
         kError() << i18n("No backend could be selected!");
+        emit fail();
         return;
     } else {
         kDebug() << m_backend->id();