Touchpad buttons problem

I am having a strange problem with my Dell Laptop inspiron 1525. My right button on the touchpad is not working. I tried the settings in touchpad to make sure the buttons are enabled, and also restored my system to make sure there was no corruption in any of the driver files (also I suspected I may have some virus). Inspite of all that, I still not able to make the right button work. My left button works though and also the scroll.

When I checked the device manager, it says the Dell Touchpad device is working properly. How do I check if my button has gone bad or is it some sort of s/w issue.
Secondly, is that even possible that one button does not work while the other does.

I appreciate your help to this matter, and looking forward for the response.

Thanks,
Raj