I have a form with one grid having some data which is grouped on one column, i wanted to make particular group editable or readonly based on button click.

I am not able to access the cells in this group in grid rows collection so that i can change using activation property.

Can somebody please help me in this regard?

If the grid is grouped, then the rows collection will be a hierarchy with the GroupByRows at the top and the data rows underneath.

Basically, you probably have to find the GroupByRow in the root-level rows collection the then cast it into an UltraGridGroupByRow, then access the Rows collection on the UltraGridGroupByRow to get the child rows. Of course, the child rows could be GroupByRows, too, if you have more than one column of grouping.

A better way to do things with rows and cells is to use the InitializeRow event of the grid.

But it's really hard to tell you how to get to the data rows without knowing what criteria you are using.