Microsoft Visual Studio Object reference not set

Here is a strange error message which appears only on my PC. Hope someone has a solution for this.
I have Windows Vista operating system on which Microsoft Visual 2008 is installed. I have been working on a project for some time and when I try to right click on the particular project and import DataBase schema, I get the object reference error message.
Microsoft Visual Studio
Object reference not set to an instance of an object.
I have tried to perform the same action on one of my friends PC and that seems to work fine.
Any ideas?
