diff --git a/reactos/include/psdk/wintrust.h b/reactos/include/psdk/wintrust.h
index 6ec3c405cdb..228d868d8c4 100644
--- a/reactos/include/psdk/wintrust.h
+++ b/reactos/include/psdk/wintrust.h
@@ -371,7 +371,7 @@ typedef struct _CRYPT_PROVIDER_DATA {
 #define CPD_UISTATE_MODE_ALLOW  0x00000002
 #define CPD_UISTATE_MODE_MASK   0x00000003
 
-typedef BOOL (CALLBACK *PFN_PROVUI_CALL)(HWND hWndSecurityDialog,
+typedef BOOL (*PFN_PROVUI_CALL)(HWND hWndSecurityDialog,
  struct _CRYPT_PROVIDER_DATA *pProvData);
 
 typedef struct _CRYPT_PROVUI_FUNCS {