diff --git a/ScStwLibraries/sources/scstwsettings.cpp b/ScStwLibraries/sources/scstwsettings.cpp
index 81c843c..fa372ea 100644
--- a/ScStwLibraries/sources/scstwsettings.cpp
+++ b/ScStwLibraries/sources/scstwsettings.cpp
@@ -74,14 +74,21 @@ bool ScStwSettings::setDefaultSetting(int key, int keyLevel, QVariant defaultVal
 QVariant ScStwSettings::readSetting(QString key, int keyInt, int keyLevel) {
     Q_UNUSED(keyInt)
     Q_UNUSED(keyLevel)
-    return this->settingsCache[key];
+
+    if(this->settingsCache.contains(key))
+        return this->settingsCache[key];
+    else
+        return QVariant();
 }
 
 bool ScStwSettings::writeSetting(QString key, QVariant value, int keyInt, int keyLevel) {
-    if(!this->keyToTypeConverters.contains(keyInt) || !value.convert(this->keyToTypeConverters[keyLevel](keyInt)) || value.type() == QVariant::Invalid) {
+
+    // check if the value type is valid
+    if(!this->keyToTypeConverters.contains(keyLevel) || !value.convert(this->keyToTypeConverters[keyLevel](keyInt)) || value.type() == QVariant::Invalid) {
         return false;
     }
 
+    // write the setting
     if(!this->settingsCache.contains(key))
         this->settingsCache.insert(key, value);
     else if (this->settingsCache[key] == value)