---
title: "Failed zone transfers from BIND 9 to Windows 2000"
slug: "aa-00330"
description: "These failures may be caused by a bug in the Windows 2000 DNS server which caused DNS messages larger than 16KB to be handled incorrectly."
updated: 2021-06-21T21:44:29Z
published: 2021-06-21T21:44:29Z
canonical: "kb.isc.org/aa-00330"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://kb.isc.org/llms.txt
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# Zone transfers from my BIND 9 primary to my Windows 2000 secondary fail. Why?

This may be caused by a bug in the Windows 2000 DNS server which caused DNS messages larger than 16KB to be handled incorrectly. This bug can be worked around by setting the option `transfer-format one-answer;` on the BIND 9 primary server.

Also check whether your zone contains domain names with embedded spaces or other special characters, like "John\032Doe\213s\032Computer", since such names have been known to cause Windows 2000 secondaries to incorrectly reject the zone.