diff --git a/src/Gui/DownloadDialog.cpp b/src/Gui/DownloadDialog.cpp
index 49a660c93..979e092ea 100644
--- a/src/Gui/DownloadDialog.cpp
+++ b/src/Gui/DownloadDialog.cpp
@@ -23,6 +23,8 @@
 
 #include "PreCompiled.h"
 #ifndef _PreComp_
+# include <QPushButton>
+# include <QHBoxLayout>
 #endif
 
 #include "DownloadDialog.h"
diff --git a/src/Gui/DownloadDialog.h b/src/Gui/DownloadDialog.h
index ce488a85d..36bcb9b33 100644
--- a/src/Gui/DownloadDialog.h
+++ b/src/Gui/DownloadDialog.h
@@ -30,12 +30,15 @@
 #include <QBuffer>
 #include <QLabel>
 #include <QProgressBar>
-#include <QProgressDialog>
 #include <QHttp>
 #include <QFileInfo>
 #include <QCloseEvent>
 #include <QDialogButtonBox>
 
+class QFile;
+class QHttpResponseHeader;
+class QAuthenticator;
+
 namespace Gui {
 namespace Dialog {