[From SQL Server Central
In this article I want to show you one tricky issue I faced recently. This took around 6 hours to track down what exactly was happening and hence I am sharing the details so that if you have the same problem it will be a quick check for you instead of hours.
My client environment is not totally upgraded to SQL Server 2005, and I still have a few SQL Server 2000 servers in my environment. On one such SQL Server 2000 server I received the request to install SP4. SP4, which is usually a cakewalk to install, failed.
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