diff --git a/Texconv/texconv.cpp b/Texconv/texconv.cpp
index 9e99456..1a508d4 100644
--- a/Texconv/texconv.cpp
+++ b/Texconv/texconv.cpp
@@ -1184,7 +1184,7 @@ int __cdecl wmain(_In_ int argc, _In_z_count_(argc) wchar_t* argv[])
         else if (wcspbrk(pArg, L"?*") != nullptr)
         {
             size_t count = conversion.size();
-            SearchForFiles(pArg, conversion, (dwOptions & (1 << OPT_RECURSIVE)) != 0);
+            SearchForFiles(pArg, conversion, (dwOptions & (DWORD64(1) << OPT_RECURSIVE)) != 0);
             if (conversion.size() <= count)
             {
                 wprintf(L"No matching files found for %ls\n", pArg);