Full Factory Recovery

This option completely erases the C: partition and reinstalls factory-shipped files from the recovery partition.

Note: All of your personal data files and applications will be lost. Be sure that you have your data files backed up before performing this option.

Note: Due to the large number of virus and Spyware threats on the Internet, it is recommended that you disconnect all Internet connections before reinstalling Windows®. After the Windows installation, antivirus and firewall software can be installed and then the Internet connection can be re-enabled to update the antivirus definitions and perform Windows Updates.

1. Remove all CDs or DVDs from the optical drives.
   
   
2. Turn off the computer, using the normal Windows shut down process.
   
   
3. After the computer is turned off, disconnect all USB devices except the keyboard and mouse. This includes USB devices such as a printer, scanner, removable storage, or camera.
   
   
4. Turn on the computer. After the Gateway BIOS logo appears, repeatedly press the F8 key. The Advanced Boot Options menu opens.
   
   
5. On the Advanced Boot Options screen, use the arrow keys to select Repair your Computer, and then press the ENTER key.
   
   
6. In the System Recovery Options dialog box, select the appropriate keyboard layout, and then click Next.
   
   
7. In the System Recovery Options dialog box, click the down arrow to select a user account that has Administrator rights, then click OK.
   
   Note: The Administrator account is disabled by default.
   
   
8. In the System Recovery Options window, select Recovery Manager.
   
   
9. In the Gateway Recovery Center window, click Next.
   
   
10. In the Gateway system recovery window, select Full factory recovery.
    
    
11. In the All data will be lost window, select Yes, and then click Next.
    
    
12. The Windows partition is formatted and Windows is installed.
    
    
13. In the Recovery is complete window, click Finish.
    
    
14. In the System Recovery Options window, select Restart.
    
    
15. The computer restarts.
    
    
16. Windows prepares to start for the first time. This may take a few minutes.
    
    
17. Drivers and applications are installed. This process will take several minutes. The more drivers and applications that need to be installed, the longer the process will take.
    
    Note: The following Out of Box Experience (OOBE) screens may vary slightly between computer models.
    
    
18. In the Set Up Windows screen, select the appropriate options and then click Next.
    
    
19. In the Please read the license terms screen, check I accept the license terms, and then click Next.
    
    
20. In the Choose a user name and picture screen, enter the appropriate information and then click Next.
    
    
21. In the Type a computer name and choose a desktop background screen, enter the appropriate information, and then click Next.
    
    
22. In the Help protect Windows automatically screen, select Use recommended settings.
    
    
23. In the Review your time and date settings screen, enter the appropriate information and then click Next.
    
    
24. In the Thank You screen, click Start.
    
    
25. Windows checks the computer's performance. Depending on hardware, this process could take from 3 to 15 minutes to complete.
    
    
26. Windows prepares the desktop.
    
    
27. Installation is complete. Any application that shipped on a separate CD can now be installed. It is recommended to update the antivirus definitions and perform Windows Updates. 

Note - Got solution from Gateway web site "http://support.gateway.com/s/software/MICROSOF/vista/7515418/7515418su531.shtml"