diff --git a/lib/http_ntlm.h b/lib/http_ntlm.h
index 6dad32d13..c80bb09ff 100644
--- a/lib/http_ntlm.h
+++ b/lib/http_ntlm.h
@@ -50,6 +50,6 @@ void Curl_http_ntlm_cleanup(struct connectdata *conn);
 #define Curl_http_ntlm_cleanup(x)
 #endif
 
-#include <curl_ntlm.h>
+#include "curl_ntlm.h"
 
 #endif /* HEADER_CURL_HTTP_NTLM_H */