--- c:\Qt\qt-everywhere-enterprise-src-5.9.1\qtbase\src\widgets\dialogs\qfilesystemmodel.cpp	Wed Jun 28 09:54:29 2017 UTC
+++ c:\Qt\5.9.1\qtbase\src\widgets\dialogs\qfilesystemmodel.cpp	Wed Nov 1 07:59:07 2017 UTC
@@ -386,7 +386,10 @@
             trailingSeparator = QLatin1String("\\");
         int r = 0;
         QFileSystemModelPrivate::QFileSystemNode *rootNode = const_cast<QFileSystemModelPrivate::QFileSystemNode*>(&root);
-        if (!root.children.contains(host.toLower())) {
+		bool needsAdd = !root.children.contains(host);
+        if (needsAdd && !root.caseSensitive())
+	        needsAdd = !root.children.contains(host.toLower());
+        if (needsAdd) {
             if (pathElements.count() == 1 && !absolutePath.endsWith(QLatin1Char('/')))
                 return rootNode;
             QFileInfo info(host);