Unhandled exception

Question

Dear All,
           I,m recording a video on button click.If i record morethan 3 times continously on button click it was throwing an exception.The generated exception was: Unhandled exception at 0x00000000 in myapp.exe: 0xC0000000: Access violation reading location 0x00000000.Can any one help me how to solve this problem?.

Thanks in advance.