I have had problem when installing SQL Server 2005 on one of the 64-bit server, the error was: There was an unexpected failure during the setup wizard. You may review the setup logs and/or click the help button for more information. So as per the message I have looked in to the specified directory for the logs which is " C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files" and only error I could see is: Error Code: 0x80070643 (1603) Windows Error Text: Fatal error during installation....(
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