I have installed SQL Server 2008 R2 installed on my PC. Now I want to add the Database Engine Service but I get 'The system cannot find the file specified' error. I did this through control panel>uninstall program> add. I get various errors.

TITLE: Microsoft SQL Server 2008 R2 Setup
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The following error has occurred:

SQL Server Setup has encountered an error when running a Windows Installer file.

Windows Installer error message: The system cannot find the file specified.

Windows Installer file: D:\Files\SQL Server 2008 R2 Enterprise (x86 x64 ia64) - DVD (English)\1033_ENU_LP\x86\setup\x86\SqlWriter.msi
Windows Installer log file: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20120426_210629\SqlWriter_Cpu32_1.lo g

Click 'Retry' to retry the failed action, or click 'Cancel' to cancel this action and continue setup.

For help, click: Source: setup.rll ID: 50000 (SQL Server 10.50.1600.1) - Events And Errors Message Center: Message Details

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BUTTONS:

&Retry
Cancel
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TITLE: Microsoft SQL Server 2008 R2 Setup
------------------------------

The following error has occurred:

Error reading from file: D:\Files\SQL Server 2008 R2 Enterprise (x86 x64 ia64) - DVD (English)\x86\setup\sql_engine_core_shared_msi\PFi les\SqlServr\100\COM\iftsph.dll. Verify that the file exists and that you can access it.

For help, click: Source: ID: ( ) - Events And Errors Message Center: Message Details

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BUTTONS:

OK
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TITLE: Microsoft SQL Server 2008 R2 Setup
------------------------------

The following error has occurred:

SQL Server Setup has encountered an error when running a Windows Installer file.

Windows Installer error message: The system cannot find the file specified.

Windows Installer file: D:\Files\SQL Server 2008 R2 Enterprise (x86 x64 ia64) - DVD (English)\x86\setup\RsFx.msi
Windows Installer log file: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20120426_210629\RsFx_Cpu32_1.log

Click 'Retry' to retry the failed action, or click 'Cancel' to cancel this action and continue setup.

For help, click: Source: setup.rll ID: 50000 (SQL Server 10.50.1600.1) - Events And Errors Message Center: Message Details

------------------------------
BUTTONS:

&Retry
Cancel
------------------------------


TITLE: Microsoft SQL Server 2008 R2 Setup
------------------------------

The following error has occurred:

SQL Server Setup has encountered an error when running a Windows Installer file.

Windows Installer error message: The system cannot find the file specified.

Windows Installer file: D:\Files\SQL Server 2008 R2 Enterprise (x86 x64 ia64) - DVD (English)\x86\redist\watson\dw20shared.msi
Windows Installer log file: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Log\20120427_093341\WatsonX86_Cpu32_1_Co mponentUpdate.log

Click 'Retry' to retry the failed action, or click 'Cancel' to cancel this action and continue setup.

For help, click: Source: setup.rll ID: 50000 (SQL Server 10.50.1600.1) - Events And Errors Message Center: Message Details

------------------------------
BUTTONS:

&Retry
Cancel
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