While creating Xstep, In order to assign the characteristics to parameters shows an error "characteristic - Data type has not yet been determined"

Hi Experts,

While creating Xstep, In order to assign the characteristics to parameters shows an error "characteristic - Data type has not yet been determined"

I checked out in possible enteries , It shows that some of the characteristics are already maintained but It is not displayed during assignment. I checked out max no of threads.. Though there is no relevant data.. Pls help me.. Thanks in advance for replies....