SQL Server 2005 Installation Problem?

summary.txt looks like this:

Microsoft SQL Server 2005 9.00.1399.06
==============================
OS Version : Microsoft Windows XP Professional Service Pack 2 (Build 2600)
Time : Fri Nov 25 22:42:40 2005
P2 : The current system does not meet recommended hardware requirements for this SQL Server release. For detailed hardware requirements, see the readme file or SQL Server Books Online.
Machine : P2
Product : Microsoft SQL Server Setup Support Files (English)
Product Version : 9.00.1399.06
Install : Successful
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_SQLSupport_1.log
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Machine : P2
Product : Microsoft SQL Server Native Client
Product Version : 9.00.1399.06
Install : Successful
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_SQLNCLI_1.log
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Machine : P2
Product : Microsoft SQL Server VSS Writer
Product Version : 9.00.1399.06
Install : Successful
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_SqlWriter_1.log
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Machine : P2
Product : MSXML 6.0 Parser
Product Version : 6.00.3883.8
Install : Successful
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_MSXML6_1.log
--
Machine : P2
Product : Microsoft SQL Server Setup Support Files (English)
Product Version : 9.00.1399.06
Install : Successful
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_SQLSupport_2.log
--
Machine : P2
Product : Microsoft SQL Server Native Client
Product Version : 9.00.1399.06
Install : Successful
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_SQLNCLI_2.log
--
Machine : P2
Product : MSXML 6.0 Parser
Product Version : 6.00.3883.8
Install : Successful
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_MSXML6_2.log
--
Machine : P2
Product : SQL Server Database Services
Error : An instance with the same name is already installed on this computer. To proceed with SQL Server Setup, provide a unique instance name.
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Machine : P2
Product : SQL Server Database Services
Error : An instance with the same name is already installed on this computer. To proceed with SQL Server Setup, provide a unique instance name.
--
Machine : P2
Product : Microsoft SQL Server 2005 Express Edition
Product Version : 9.00.1399.06
Install : Failed
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_SQL.log
Last Action : DetectInstanceClash
Error String : An instance with the same name is already installed on this computer. To proceed with SQL Server Setup, provide a unique instance name.
Error Number : 28086
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Machine : P2
Product : Microsoft SQL Server 2005 Tools Express Edition
Product Version : 9.00.1399.06
Install : Successful
Log File : C:\Program Files\Microsoft SQL Server\90\Setup Bootstrap\LOG\Files\SQLSetup0011_P2_Tools.log
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SQL Server Setup failed. For more information, review the Setup log file in %ProgramFiles%\Microsoft SQL Server\90\Setup Bootstrap\LOG\Summary.txt.