diff --git a/dlls/advpack/advpack.c b/dlls/advpack/advpack.c
index d904d3af5b2..b3fde0556cf 100644
--- a/dlls/advpack/advpack.c
+++ b/dlls/advpack/advpack.c
@@ -392,6 +392,21 @@ HRESULT WINAPI ExecuteCab( HWND hwnd, PCABINFO pCab, LPVOID pReserved )
     return E_FAIL;
 }
 
+/***********************************************************************
+ *             ExtractFiles    (ADVPACK.@)
+ *
+ * BUGS
+ *   Unimplemented
+ */
+
+HRESULT WINAPI ExtractFiles ( LPCSTR CabName, LPCSTR ExpandDir, DWORD Flags,
+                              LPCSTR FileList, LPVOID LReserved, DWORD Reserved)
+{
+    FIXME("(%p %p 0x%08lx %p %p 0x%08lx): stub\n", CabName, ExpandDir, Flags, 
+          FileList, LReserved, Reserved);
+    return E_FAIL;
+}
+
 /***********************************************************************
  *             TranslateInfString    (ADVPACK.@)
  *
diff --git a/dlls/advpack/advpack.spec b/dlls/advpack/advpack.spec
index 915e80ad464..0c792b2b81e 100644
--- a/dlls/advpack/advpack.spec
+++ b/dlls/advpack/advpack.spec
@@ -6,7 +6,7 @@
 @ stdcall -private DllMain(long long ptr)
 @ stdcall DoInfInstall(ptr)
 @ stdcall ExecuteCab(ptr ptr ptr)
-@ stub ExtractFiles
+@ stdcall ExtractFiles(str str long ptr ptr long)
 @ stub FileSaveMarkNotExist
 @ stub FileSaveRestore
 @ stub FileSaveRestoreOnINF