Common failures and resolutions during SQL Server installation - Part 1

Some times SQL Server installation will fail due to many reasons .

I would like to add the generic error and resolution .

Problem 1:

When you try to install Microsoft SQL Server 2008 on a server, the installation fails. When you try to reinstall the same copy of SQL Server 2008 on the same server, this installation also fails.

Rout Cause :

This problem occurs because after the first installation fails, a partly installed instance of SQL Server 2008 exists on the server. The SQL Server 2008 Setup program does not roll back the installation if the installation fails. The partly installed instance does not include the edition of SQL Server 2008 that you were trying to install, such as

the Enterprise edition, the Standard edition, or the Evaluation edition. When you try to install the same version on the same server, the Setup program finds the existing instance. However, the Setup program cannot determine which version of SQL Server 2008 to install. Therefore, the installation fails.

Solution :

To resolve this issue, you must uninstall the previous instance of SQL Server 2008 before you try to install SQL Server 2008 again on the same server.

To uninstall SQL Server 2008 by using Add or Remove Programs, follow these steps.

On Windows 7

1. Click Start, click Run, type appwiz.cpl, and then press ENTER.
2. In the list of installed programs, click Microsoft SQL Server 2008, and then click Uninstall.
3. Follow the instructions that appear on the screen to uninstall SQL Server 2008.

On Windows Server 2003

1. Click Start, click Run, type appwiz.cpl, and then press ENTER.
2. In the list of installed programs, click Microsoft SQL Server 2008, and then click Uninstall.
3. Follow the instructions that appear on the screen to uninstall SQL Server 2008.

On Windows Server 2008

1. Click Start, type appwiz.cpl in the Start Search box, and then press ENTER.
2. In the list of installed programs, click Microsoft SQL Server 2008, and then click Uninstall.
3. Follow the instructions that appear on the screen to uninstall SQL Server 2008. 
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