You can try the following methods:
Method 1:
Use Startup Repair to try to repair any startup issues with your computer
Startup Repair will try to repair any startup issues in Windows 7. To run the Startup Repair tool, follow these steps:
a) Restart your computer and start pressing the F8 key on your keyboard. You need to press F8 before the Windows logo appears. If the Windows logo appears, you need to try again by waiting until the Windows logon prompt appears, and then shutting down and restarting your computer.
Note: On a computer that is configured for booting to multiple operating systems, you can press the F8 key when the Boot Menu appears
b) Use the arrow keys to choose Repair your Computer in the Advanced Boot Options and then press ENTER. If prompted, select the Windows 7 installation to be repaired, and then click Next
c) Select the Language and a keyboard input method and click Next
d) Select a User name and type your Password and click OK
e) Under System Recovery Options, click Startup Repair.
Note: If the repair process detects a problem when it starts Windows 7, it will run Startup Repair to automatically fix the problems. Allow this process to complete. Startup Repair might prompt you to make choices as it tries to fix the problem, and if necessary, it might restart your computer as it makes repairs.
f) On the Startup Repair window click Finish
g) Restart your computer if prompted
Quote