diff --git a/Modules/_ssl.c b/Modules/_ssl.c
index f84ef92..6b43d22 100644
--- a/Modules/_ssl.c
+++ b/Modules/_ssl.c
@@ -3080,7 +3080,7 @@
         return NULL;
     }
 
-    if ((hStore = CertOpenSystemStore(NULL, store_name)) == NULL) {
+    if ((hStore = CertOpenSystemStore((HCRYPTPROV)NULL, store_name)) == NULL) {
         Py_DECREF(result);
         return PyErr_SetFromWindowsErr(GetLastError());
     }