diff --git a/source/g3d_viewer/main.cpp b/source/g3d_viewer/main.cpp
index 0d3c9d8d0..2d393548c 100644
--- a/source/g3d_viewer/main.cpp
+++ b/source/g3d_viewer/main.cpp
@@ -455,7 +455,8 @@ MainWindow::MainWindow(	std::pair<string,vector<string> > unitToLoad,
 	auto_ptr<wchar_t> wstr(Ansi2WideString(appPath.c_str()));
 	
 	wstring launchApp = wstring(wstr.get()) + L" \"%1\"";
-	DWORD len = (DWORD)launchApp.length() + 1;
+	//DWORD len = (DWORD)launchApp.length() + 1;
+	DWORD len = (launchApp.size() + 1) * sizeof(wchar_t);
 	RegSetValueEx(keyHandle, NULL, 0, REG_SZ, (PBYTE)launchApp.c_str(), len);
 	RegCloseKey(keyHandle);
 
@@ -463,7 +464,8 @@ MainWindow::MainWindow(	std::pair<string,vector<string> > unitToLoad,
 	RegCreateKeyEx(HKEY_CURRENT_USER,subKey.c_str(),0, NULL, 0, KEY_ALL_ACCESS, NULL, &keyHandle, &dwDisposition);
 	//Set the value.
 	launchApp = L"megaglest.g3d";
-	len = (DWORD)launchApp.length() + 1;
+	//len = (DWORD)launchApp.length() + 1;
+	len = (launchApp.size() + 1) * sizeof(wchar_t);
 	RegSetValueEx(keyHandle, NULL, 0, REG_SZ, (PBYTE)launchApp.c_str(), len);
 	RegCloseKey(keyHandle);