diff --git a/src/libkst/datasource.cpp b/src/libkst/datasource.cpp
index c301e9b8f..9db7d72e3 100644
--- a/src/libkst/datasource.cpp
+++ b/src/libkst/datasource.cpp
@@ -249,6 +249,9 @@ void DataSource::checkUpdate() {
 
 
 void DataSource::deleteDependents() {
+  foreach (const PrimitivePtr &p, slavePrimitives) {
+    store()->removeObject(p);
+  }
 }
 
 
diff --git a/src/libkst/datasource.h b/src/libkst/datasource.h
index 8380783c7..c219b0345 100644
--- a/src/libkst/datasource.h
+++ b/src/libkst/datasource.h
@@ -217,6 +217,8 @@ class KSTCORE_EXPORT DataSource : public Object
     */
     virtual ObjectList<Object> autoCurves(ObjectStore&) { return ObjectList<Object>(); }
 
+    PrimitiveList slavePrimitives;
+
 
   public Q_SLOTS:
     virtual void checkUpdate();
@@ -274,6 +276,7 @@ class KSTCORE_EXPORT DataSource : public Object
     QFileSystemWatcher *_watcher;
 
     QColor _color;
+
     // NOTE: You must bump the version key if you add new member variables
     //       or change or add virtual functions.
 };
diff --git a/src/libkst/datasourcepluginmanager.cpp b/src/libkst/datasourcepluginmanager.cpp
index fbddcee3c..6ac84e237 100644
--- a/src/libkst/datasourcepluginmanager.cpp
+++ b/src/libkst/datasourcepluginmanager.cpp
@@ -295,6 +295,7 @@ DataSourcePtr DataSourcePluginManager::findPluginFor(ObjectStore *store, const Q
           s->setProvider(plugin);
           s->setSlaveName(key);
           s->setValue(value);
+          plugin->slavePrimitives.append(s);
         }
       }
 
@@ -308,6 +309,7 @@ DataSourcePtr DataSourcePluginManager::findPluginFor(ObjectStore *store, const Q
           ScalarPtr s = store->createObject<Scalar>();
           s->setProvider(plugin);
           s->setSlaveName(key);
+          plugin->slavePrimitives.append(s);
           s->setValue(value);
         }
       }
diff --git a/src/libkst/objectstore.cpp b/src/libkst/objectstore.cpp
index 1b52665da..17dd327c8 100644
--- a/src/libkst/objectstore.cpp
+++ b/src/libkst/objectstore.cpp
@@ -57,15 +57,9 @@ bool ObjectStore::removeObject(Object *o) {
   DataSourcePtr ds = kst_cast<DataSource>(o);
   if (ds) {
     if (!_dataSourceList.contains(ds)) {
-#if NAMEDEBUG > 1
-      qDebug() << "Trying to delete a non-existent data source from the store: " << ds->tag().tagString();
-#endif
       return false;
     }
   } else if (!_list.contains(o)) {
-#if NAMEDEBUG > 1
-    qDebug() << "Trying to delete a non-existent object from the store: " << o->tag().tagString();
-#endif
     return false;
   }
 
@@ -139,6 +133,9 @@ void ObjectStore::cleanUpDataSourceList() {
   for (DataSourceList::Iterator it = currentSourceList.begin(); it != currentSourceList.end(); ++it) {
     if ((*it)->getUsage() <= 1) {
       removeObject(*it);
+      //qDebug() << "remove" << (*it)->fileName() << "usage" << (*it)->getUsage();
+    } else {
+      //qDebug() << "  keep" << (*it)->fileName() << "usage" << (*it)->getUsage();
     }
   }
   currentSourceList.clear();
diff --git a/src/libkstapp/changefiledialog.cpp b/src/libkstapp/changefiledialog.cpp
index 4ff7abf2e..1f78e1fd1 100644
--- a/src/libkstapp/changefiledialog.cpp
+++ b/src/libkstapp/changefiledialog.cpp
@@ -66,6 +66,7 @@ ChangeFileDialog::ChangeFileDialog(QWidget *parent)
 
   connect(_duplicateSelected, SIGNAL(toggled(bool)), _duplicateDependents, SLOT(setEnabled(bool)));
   connect(_dataFile, SIGNAL(changed(const QString &)), this, SLOT(fileNameChanged(const QString &)));
+  connect(_dataFile, SIGNAL(destroyed()), kstApp->mainWindow(), SLOT(cleanUpDataSourceList()));
 
   connect(_buttonBox->button(QDialogButtonBox::Cancel), SIGNAL(clicked()), this, SLOT(reject()));
   connect(_buttonBox->button(QDialogButtonBox::Ok), SIGNAL(clicked()), this, SLOT(OKClicked()));
@@ -144,6 +145,8 @@ void ChangeFileDialog::sourceValid(QString filename, int requestID) {
   updateButtons();
   _configure->setEnabled(_dataSource->hasConfigWidget());
 
+  _store->cleanUpDataSourceList();
+
 }
 
 
diff --git a/src/libkstapp/datamanager.cpp b/src/libkstapp/datamanager.cpp
index 4ab3fcf6f..005be3e90 100644
--- a/src/libkstapp/datamanager.cpp
+++ b/src/libkstapp/datamanager.cpp
@@ -503,6 +503,7 @@ void DataManager::purge() {
   do {
     setUsedFlags();
   } while (_doc->objectStore()->deleteUnsetUsedFlags());
+  _doc->objectStore()->cleanUpDataSourceList();
   UpdateServer::self()->requestUpdateSignal();
   _session->reset();
 }
diff --git a/src/libkstapp/datawizard.cpp b/src/libkstapp/datawizard.cpp
index 4e5a359dc..8f7ec40c5 100644
--- a/src/libkstapp/datawizard.cpp
+++ b/src/libkstapp/datawizard.cpp
@@ -740,6 +740,7 @@ DataWizard::DataWizard(QWidget *parent, const QString& fileToOpen)
 
   connect(_pageDataSource, SIGNAL(dataSourceChanged()), _pageVectors, SLOT(updateVectors()));
   connect(_pageDataSource, SIGNAL(dataSourceChanged()), _pageDataPresentation, SLOT(updateVectors()));
+  connect(_pageDataSource, SIGNAL(destroyed()), kstApp->mainWindow(), SLOT(cleanUpDataSourceList()));
   disconnect(button(QWizard::FinishButton), SIGNAL(clicked()), (QDialog*)this, SLOT(accept()));
   connect(button(QWizard::FinishButton), SIGNAL(clicked()), this, SLOT(finished()));
 
diff --git a/src/libkstapp/mainwindow.cpp b/src/libkstapp/mainwindow.cpp
index cb12374f3..4c7a7c524 100644
--- a/src/libkstapp/mainwindow.cpp
+++ b/src/libkstapp/mainwindow.cpp
@@ -2028,6 +2028,10 @@ void MainWindow::dropEvent(QDropEvent *event)
    event->accept();
 }
 
+void MainWindow::cleanUpDataSourceList() {
+  _doc->objectStore()->cleanUpDataSourceList();
+}
+
 #if defined(__QNX__)
 bool MainWindow::eventFilter(QObject *obj, QEvent *event) {
   if (!qApp->activeWindow()) {
diff --git a/src/libkstapp/mainwindow.h b/src/libkstapp/mainwindow.h
index 1189dcf08..8c78fc4ef 100644
--- a/src/libkstapp/mainwindow.h
+++ b/src/libkstapp/mainwindow.h
@@ -107,6 +107,7 @@ class MainWindow : public QMainWindow
     void open();
     void newDoc(bool force=false);
     void openFile(const QString &file);
+    void cleanUpDataSourceList();
 #ifndef KST_NO_PRINTER
     void print();
     void setPrinterDefaults(QPrinter *printer);
diff --git a/src/libkstapp/matrixdialog.cpp b/src/libkstapp/matrixdialog.cpp
index 591239f2e..6d67700db 100644
--- a/src/libkstapp/matrixdialog.cpp
+++ b/src/libkstapp/matrixdialog.cpp
@@ -13,6 +13,7 @@
 #define NO_GENERATED_OPTIONS
 
 #include "matrixdialog.h"
+#include "application.h"
 
 #include "dialogpage.h"
 #include "datasourcedialog.h"
@@ -550,6 +551,8 @@ void MatrixTab::sourceValid(QString filename, int requestID) {
 
   validating = false;
 
+  _store->cleanUpDataSourceList();
+
   emit sourceChanged();
 }
 
@@ -625,6 +628,8 @@ MatrixDialog::MatrixDialog(ObjectPtr dataObject, QWidget *parent)
   connect(this, SIGNAL(editMultipleMode()), this, SLOT(editMultipleMode()));
   connect(this, SIGNAL(editSingleMode()), this, SLOT(editSingleMode()));
   connect(_matrixTab, SIGNAL(modified()), this, SLOT(modified()));
+  connect(_matrixTab, SIGNAL(destroyed()), kstApp->mainWindow(), SLOT(cleanUpDataSourceList()));
+
   updateButtons();
 }
 
diff --git a/src/libkstapp/scalardialog.cpp b/src/libkstapp/scalardialog.cpp
index 30f8d3c84..8ba473695 100644
--- a/src/libkstapp/scalardialog.cpp
+++ b/src/libkstapp/scalardialog.cpp
@@ -11,6 +11,8 @@
  ***************************************************************************/
 
 #include "scalardialog.h"
+#include "application.h"
+
 #include "datasourcedialog.h"
 
 #include "enodes.h"
@@ -203,6 +205,8 @@ void ScalarTab::sourceValid(QString filename, int requestID) {
 
   _dataSource->unlock();
   modified();
+
+  _store->cleanUpDataSourceList();
   emit sourceChanged();
 }
 
@@ -251,6 +255,7 @@ ScalarDialog::ScalarDialog(ObjectPtr dataObject, QWidget *parent)
 
   connect(_scalarTab, SIGNAL(valueChanged()), this, SLOT(updateButtons()));
   connect(_scalarTab, SIGNAL(valueChanged()), this, SLOT(modified()));
+  connect(_scalarTab, SIGNAL(destroyed()), kstApp->mainWindow(), SLOT(cleanUpDataSourceList()));
   updateButtons();
 }
 
@@ -346,6 +351,8 @@ ObjectPtr ScalarDialog::createNewGeneratedScalar(){
   _dataObjectName = scalar->Name();
 
   //UpdateServer::self()->requestUpdateSignal();
+  _scalarTab->setDataSource(0L);
+  _document->objectStore()->cleanUpDataSourceList();
 
   return static_cast<ObjectPtr>(scalar);
 }
diff --git a/src/libkstapp/stringdialog.cpp b/src/libkstapp/stringdialog.cpp
index 5232516fc..f6eedba59 100644
--- a/src/libkstapp/stringdialog.cpp
+++ b/src/libkstapp/stringdialog.cpp
@@ -11,6 +11,7 @@
  ***************************************************************************/
 #include "stringdialog.h"
 
+#include "application.h"
 #include "datasourcedialog.h"
 #include "enodes.h"
 #include "document.h"
@@ -164,8 +165,10 @@ void StringTab::sourceValid(QString filename, int requestID) {
   _configure->setEnabled(_dataSource->hasConfigWidget());
 
   _dataSource->unlock();
+
+  _store->cleanUpDataSourceList();
+
   emit sourceChanged();
-//   emit valueChanged();
 }
 
 
@@ -210,6 +213,7 @@ StringDialog::StringDialog(ObjectPtr dataObject, QWidget *parent)
 
   connect(_stringTab, SIGNAL(valueChanged()), this, SLOT(updateButtons()));
   connect(_stringTab, SIGNAL(sourceChanged()), this, SLOT(updateButtons()));
+  connect(_stringTab, SIGNAL(destroyed()), kstApp->mainWindow(), SLOT(cleanUpDataSourceList()));
   updateButtons();
 }
 
@@ -281,7 +285,8 @@ ObjectPtr StringDialog::createNewGeneratedString(){
 
   _dataObjectName = string->Name();
 
-  //UpdateServer::self()->requestUpdateSignal();
+  _stringTab->setDataSource(0L);
+  _document->objectStore()->cleanUpDataSourceList();
 
   return static_cast<ObjectPtr>(string);
 }
diff --git a/src/libkstapp/vectordialog.cpp b/src/libkstapp/vectordialog.cpp
index ab51899ff..b88a280b7 100644
--- a/src/libkstapp/vectordialog.cpp
+++ b/src/libkstapp/vectordialog.cpp
@@ -133,7 +133,6 @@ QString VectorTab::file() const {
 
 
 void VectorTab::setFile(const QString &file) {
-  QFileInfo info(file);
   _fileName->setFile(file);
 }
 
@@ -282,6 +281,8 @@ void VectorTab::sourceValid(QString filename, int requestID) {
 
   validating = false;
 
+  _store->cleanUpDataSourceList();
+
   emit sourceChanged();
 }
 
@@ -334,6 +335,7 @@ VectorDialog::VectorDialog(ObjectPtr dataObject, QWidget *parent)
   connect(this, SIGNAL(editSingleMode()), this, SLOT(editSingleMode()));
 
   connect(_vectorTab, SIGNAL(modified()), this, SLOT(modified()));
+  connect(_vectorTab, SIGNAL(destroyed()), kstApp->mainWindow(), SLOT(cleanUpDataSourceList()));
   updateButtons();
 }
 
@@ -527,6 +529,9 @@ ObjectPtr VectorDialog::createNewGeneratedVector() {
 
   _dataObjectName = vector->Name();
 
+  _vectorTab->setDataSource(0L);
+  _document->objectStore()->cleanUpDataSourceList();
+
   //UpdateServer::self()->requestUpdateSignal();
   return vector;
 }