diff --git "a/dll/win32/kernel32/client/file/rw.c" "b/dll/win32/kernel32/client/file/rw.c"
index 8fc10d2ae37..85bfcb12d52 100644
--- "a/dll/win32/kernel32/client/file/rw.c"
+++ "b/dll/win32/kernel32/client/file/rw.c"
@@ -77,6 +77,7 @@ WriteFile(IN HANDLE hFile,
     else
     {
         IO_STATUS_BLOCK Iosb;
+        Iosb.Information = 0;
 
         Status = NtWriteFile(hFile,
                              NULL,
@@ -188,6 +189,7 @@ ReadFile(IN HANDLE hFile,
     else
     {
         IO_STATUS_BLOCK Iosb;
+        Iosb.Information = 0;
 
         Status = NtReadFile(hFile,
                             NULL,