Use sony vaio SVE15126CNB laptop installed with windows 8(64-bit) OS. in mine two finger right click is found enabled by default...... but i find that whenever i boot, this works when i'm in the login screen but fails to work as the entire startup is over. i could observe it failing to work on the desktop. what's worse is that it has once failed like this before and again started working so that i couldn't think of it a mere a problem with the settings.

This issue might have caused due to any third party program or app or due to updated drivers missing. To assist you further with this issue, I would like to know some information regarding the same.

1. Do you get any error code or error message?
2. Have you made any changes to the computer prior to this issue?

I would suggest you to try the following methods and check if it works for you.
Method 1:
Run the Hardware and Devices troubleshooter and check.
Follow the steps to run the troubleshooter:
a. Press Windows key + W on your keyboard.
b. Type Troubleshooting and click Troubleshooting under Settings.
c. Now type Hardware Troubleshooter in the search option.
d. Click on Hardware and Devices troubleshooter to run the troubleshooter.

Method 2:
Place the computer in Clean Boot and check if the issue persists. Clean Boot will help you determine which third party program/app is causing this issue.

How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7: http://support.microsoft.com/kb/929135

Note: After clean boot troubleshooting step, refer to the section "How to reset the computer to start as usual after troubleshooting with clean boot" in the provided link to return your computer to Normal startup mode.

Method 3:
Try updating all the device drivers from the Sony website and check if it helps.
http://www.sony.co.in/support/product/sve15126cn/download