FSI error requesting Total Mesh Displacement
 

Hi,
I am trying to solve FSI problem using ANSYS/CFX coupling.
But I keep getting a weird error:

Fatal error requesting total mesh displacement for Interface

Here are the links to the error images:

http://docs.google.com/leaf?id=0B10p...MGMyN2M1&hl=en

http://docs.google.com/leaf?id=0B10p...YmRmMzVi&hl=en


If I run the simu again the error occurs at some other timestep, so there is no fixed pattern to it.
It happens also when I use the FSI(Oscillating plate) tutorial.
I doubt there is any error on my part since for the tutorial I am using the .pre file supplied by ANSYS itself.

Can anyone help me since I cannot get even a simple FSI problem to run.

Thanks...