>Can anyone help me. I am trying to use macro substituion in my form that has a grid. My grid needs to have particular backcolor in the dynamic mask. I attempted to use the macro sub, but it tells me invalid data type for this field. Can anyone help me. Thanks!

Read the help on DynamicBackColor, it is a cExpression. There is no need to do macro expansion. Additionally, macro expansion would really hurt performance because it would be executed before the display of ever row in the grid.