Hi all, thanks for your time. the problem is solved at my end. Problem lies in importing the type library (tlb) of the COM server in to my client application. Because of which, object gets a corrupted pointer. when a member function is called it gives ACCESS VOILATION error. I actually imported the typelibrary in my Visual C++ application using "CLASS WIZARD" as mentioned @ MSDN link: http://msdn.microsoft.com/en-us/library/aa279228(VS.60).aspx Which actually caused the above problem. Later I found by importing typelibrary using simple #import "xyz.tlb" it generates two files .tlh and .tli files which also contains all the classes and member function definitions. When i used these files in my project it worked. Sorry for bothering you...... thanks and regards sandeep r.