error in outputting data with NI board

I tried to generate a sine wave in matlab and output to a D-A converter on NI PCI(6259) board and display on DSO. I am getting an error status code as "-200294".

When iam testing analog outout using measurement and automation explorer, iam getting the output displayed on DSO but there is a problem when iam trying to run the output using matlab.

When iam inputing data from external source ( sine wave from function generator ), iam able to see the output in matlab scope.
RAM used 256MB.

Please help me out ASAP. I am new to using NI boards.
thanking you in advance.

regards
archana
.