Installig SQL Server 2012 Step by Step

1. Double click on the Setup.exe.

2. After Installation Wizard runs the SQL Server Installation Center. If you need to create a new installation of SQL Server, click Installation in the left-hand navigation area, and then click New SQL Server stand-alone installation else you need to add features to already installed server click on  add features.

3. The System Configuration Checker runs a discovery operation on your computer.If check is passed  click OK to continue. You can view the details on the screen by clicking Show Details, or you need it  as an HTML report by clicking View detailed report in opened window.

4. On the Setup Support Files page, click Install to install the Setup support files.

5. The System Configuration Checker runs a discovery operation on your computer. To continue, click OK. You can view the details on the screen by clicking Show Details. 
In here if the checker is failed 
 goto redist  folder in setup files.install that you need 

 6. On the Language Selection page, you can specify the language for your instance of SQL Server if you are installing on a localized operating system and the installation media includes language packs for both English and the language corresponding to the operating system. To continue, click Next.

If this Doesn't Work for you.
   May be you are working with Visual Studio 2010 .you have to uninstall visual Studio later version  and try again.

7. On the License Terms page, review the license agreement and, if you agree, select the I accept the license terms check box, and then click Next.

8. On the Product Updates page, the latest available SQL Server product updates are displayed. If you don't want to include the updates, clear the Include SQL Server product updates check box. If no product updates are discovered, SQL Server Setup does not display this page and auto advances to the Install Setup Files page.

 9. On the Install Setup files page, Setup provides the progress of downloading, extracting, and installing the Setup files. If an update for SQL Server Setup is found, and is specified to be included, that update will also be installed.

10. The System Configuration Checker verifies the system state of your computer before Setup continues.

11. On the Setup Role page, select SQL Server Feature Installation, and then click Next to continue to the Feature Selection page.

12. On the Feature Selection page, select the components for your installation.I recommend you to select Select all Option.

13. On the Instance Configuration page, specify whether to install a default instance or a named instance. Instance ID - By default, the instance name is used as the Instance ID.You can manually give ID also.

• Instance root directory - By default, the instance root directory is C:\Program Files\Microsoft SQL Server\110\. To specify a non-default root directory, use the field provided, or click Browse to locate an installation folder.

• Installed instances - The grid shows instances of SQL Server that are on the computer where Setup is running. If a default instance is already installed on the computer, you must install a named instance of SQL Server 2012.

14. The Disk Space Requirements page calculates the required disk space for the features that you specify.

15.  Work flow for the rest of this topic depends on the features that you have specified for your installation. You might not see all the pages, depending on your selections.

16. Use the Server Configuration — Service Accounts page to specify login accounts for SQL Server services. The actual services that are configured on this page depend on the features that you selected to install.
      Do not use a blank password. Use a strong password.

17.Use the Database Engine Configuration - Account Provisioning page to specify the following:

• Security Mode - Select Windows Authentication or Mixed Mode Authentication for your instance of SQL Server. If you select Mixed Mode Authentication, you must provide a strong password for the built-in SQL Server system administrator account.I recommended to use Mixed Mode Authentication.

• SQL Server Administrators - You must specify at least one system administrator for the instance of SQL Server. To add the account under which SQL Server Setup is running, click Add Current User. 

 

 18.The Ready to Install page shows a tree view of installation options that were specified during Setup. On this page, Setup indicates whether the Product Update feature is enabled or disabled and the final update version.
To continue, click Install.