diff --git a/src/freedombone b/src/freedombone
index 80d22a82..f969697c 100755
--- a/src/freedombone
+++ b/src/freedombone
@@ -8384,13 +8384,13 @@ function install_mediagoblin {
   sed -i "s/email_sender_address.*/email_sender_address = \"$MY_EMAIL_ADDRESS\"/g" $MEDIAGOBLIN_PATH/mediagoblin_local.ini
 
   # add extra media types
-  if grep -q "media_types.stl" $MEDIAGOBLIN_PATH/mediagoblin_local.ini; then
+  if ! grep -q "media_types.stl" $MEDIAGOBLIN_PATH/mediagoblin_local.ini; then
       echo '[[mediagoblin.media_types.stl]]' >> $MEDIAGOBLIN_PATH/mediagoblin_local.ini
   fi
-  if grep -q "media_types.audio" $MEDIAGOBLIN_PATH/mediagoblin_local.ini; then
+  if ! grep -q "media_types.audio" $MEDIAGOBLIN_PATH/mediagoblin_local.ini; then
       echo '[[mediagoblin.media_types.audio]]' >> $MEDIAGOBLIN_PATH/mediagoblin_local.ini
   fi
-  if grep -q "media_types.video" $MEDIAGOBLIN_PATH/mediagoblin_local.ini; then
+  if ! grep -q "media_types.video" $MEDIAGOBLIN_PATH/mediagoblin_local.ini; then
       echo '[[mediagoblin.media_types.video]]' >> $MEDIAGOBLIN_PATH/mediagoblin_local.ini
   fi