diff --git a/libdino/src/service/util.vala b/libdino/src/service/util.vala
index 66cee1c4..c7af9243 100644
--- a/libdino/src/service/util.vala
+++ b/libdino/src/service/util.vala
@@ -4,13 +4,13 @@ namespace Dino {
 
 public class Util {
     #if _WIN32
-    [CCode (cname = "ShellExecuteA")]
+    [CCode (cname = "ShellExecuteA", cheader_filename = "windows.h")]
     private static extern int ShellExecuteA(int* hwnd, string operation, string file, string parameters, string directory, int showCmd);
 
-    [CCode (cname = "CoInitialize")]
+    [CCode (cname = "CoInitialize", cheader_filename = "windows.h")]
     private static extern int CoInitialize(void* reserved);
 
-    [CCode (cname = "CoUninitialize")]
+    [CCode (cname = "CoUninitialize", cheader_filename = "windows.h")]
     private static extern void CoUninitialize();
 
     private static int ShellExecute(string operation, string file) {