Hello,
Thank you for the reply.
Firstly, you may try booting the computer in safe mode, if that works, perform clean boot to fix the issue.
Step 1: Refer to the link to boot in safe mode.
Advanced startup options (including safe mode).
http://windows.microsoft.com/en-in/windows7/advanced-startup-options-including-safe-mode
Step 2: If you are able to boot to the computer in safe mode, I would suggest you to perform clean boot because, putting your system in Clean Boot state helps in identifying if any third party applications
or startup items are causing the issue. You need to follow the steps from the article mentioned below to perform a Clean Boot.
Refer to the link to perform clean boot.
How to perform a clean boot in Windows
http://support.microsoft.com/kb/929135
Note: Refer "How to reset the computer to start normally after clean boot troubleshooting" to reset the computer to start as normal after troubleshooting***.***
If that doesn't help then, try to perform Startup repair from WinRE and see if that helps.
To perform a startup repair using Windows 7 bootable DVD or USB drive and check if that helps.
a) Insert the installation DVD or USB and boot Windows 7 from it.
b) In the ‘Windows setup’ page select the ‘language to install’, ‘Time and currency format’ and the ‘keyboard or input method’ and click on ‘next’.
c) Click on ‘Repair your computer’ and select ‘Troubleshoot’.
d) Click on ‘Advanced options’ and select ‘Automatic Repair’ and select the operating system.
Hope this helps. Otherwise, please feel free to write us back and we will be glad to help you furthr.
Thank you