diff --git a/src/util/io/package.cpp b/src/util/io/package.cpp
index 988982ee..28d2cb8d 100644
--- a/src/util/io/package.cpp
+++ b/src/util/io/package.cpp
@@ -227,8 +227,16 @@ unique_ptr<wxInputStream> Package::openIn(const String& file) {
   FileInfos::iterator it = files.find(normalize_internal_filename(file));
   if (it == files.end()) {
     // does it look like a relative filename?
-    if (filename.find(_(".mse-")) != String::npos) {
-      throw PackageError(_ERROR_2_("file not found package like", file, filename));
+    if (size_t pos = filename.find(_(".mse-")) != String::npos) {
+      // check for nested folder
+      pos = filename.find_last_of(_("/\\"));
+      String nestedFilename = filename + filename.SubString(pos, filename.size()) + wxFileName::GetPathSeparator() + file;
+      if (wxFileExists(nestedFilename)) {
+        throw PackageError(_ERROR_1_("nested folder", filename));
+      }
+      else {
+        throw PackageError(_ERROR_2_("file not found package like", file, filename));
+      }
     }
   }
   unique_ptr<wxInputStream> stream;